Merge branch 'master' into remove-old-isobjectremove-old-isobject

* master: (226 commits)
  Real time pipeline show action
  Fix `Routable.find_by_full_path` on MySQL
  add CHANGELOG.md entry for !11138
  add tooltips to user contrib graph key
  Use an absolute path for locale path in FastGettext config
  Colorize labels in issue search field
  Fix Karma failures for jQuery deferreds
  Reduce risk of deadlocks
  Fix failing spec and eslint
  Resolve discussions
  Resolve discussions
  Dry up routable lookups. Fixes #30317
  Add “project moved” flash message on redirect
  Resolve discussions
  Fix Rubocop failures
  Index redirect_routes path for LIKE
  Add index for source association and for path
  Fix or workaround spec failure
  Refactor
  Delete conflicting redirects
  ...

79 files changed, 2251 insertions, 724 deletions

diff --git a/app/assets/javascripts/autosave.js b/app/assets/javascripts/autosave.js
index 8630b18a73f..cfab6c40b34 100644
--- a/app/assets/javascripts/autosave.js
+++ b/app/assets/javascripts/autosave.js
@@ -1,8 +1,11 @@
 /* eslint-disable func-names, space-before-function-paren, wrap-iife, no-param-reassign, quotes, prefer-template, no-var, one-var, no-unused-vars, one-var-declaration-per-line, no-void, consistent-return, no-empty, max-len */
+import AccessorUtilities from './lib/utils/accessor';
 
 window.Autosave = (function() {
   function Autosave(field, key) {
     this.field = field;
+    this.isLocalStorageAvailable = AccessorUtilities.isLocalStorageAccessSafe();
+
     if (key.join != null) {
       key = key.join("/");
     }
@@ -17,16 +20,12 @@ window.Autosave = (function() {
   }
 
   Autosave.prototype.restore = function() {
-    var e, text;
-    if (window.localStorage == null) {
-      return;
-    }
-    try {
-      text = window.localStorage.getItem(this.key);
-    } catch (error) {
-      e = error;
-      return;
-    }
+    var text;
+
+    if (!this.isLocalStorageAvailable) return;
+
+    text = window.localStorage.getItem(this.key);
+
     if ((text != null ? text.length : void 0) > 0) {
       this.field.val(text);
     }
@@ -35,27 +34,22 @@ window.Autosave = (function() {
 
   Autosave.prototype.save = function() {
     var text;
-    if (window.localStorage == null) {
-      return;
-    }
     text = this.field.val();
-    if ((text != null ? text.length : void 0) > 0) {
-      try {
-        return window.localStorage.setItem(this.key, text);
-      } catch (error) {}
-    } else {
-      return this.reset();
+
+    if (this.isLocalStorageAvailable && (text != null ? text.length : void 0) > 0) {
+      return window.localStorage.setItem(this.key, text);
     }
+
+    return this.reset();
   };
 
   Autosave.prototype.reset = function() {
-    if (window.localStorage == null) {
-      return;
-    }
-    try {
-      return window.localStorage.removeItem(this.key);
-    } catch (error) {}
+    if (!this.isLocalStorageAvailable) return;
+
+    return window.localStorage.removeItem(this.key);
   };
 
   return Autosave;
 })();
+
+export default window.Autosave;
diff --git a/app/assets/javascripts/behaviors/gl_emoji/unicode_support_map.js b/app/assets/javascripts/behaviors/gl_emoji/unicode_support_map.js
index aa522e20c36..257df55e54f 100644
--- a/app/assets/javascripts/behaviors/gl_emoji/unicode_support_map.js
+++ b/app/assets/javascripts/behaviors/gl_emoji/unicode_support_map.js
@@ -1,3 +1,5 @@
+import AccessorUtilities from '../../lib/utils/accessor';
+
 const unicodeSupportTestMap = {
   // man, student (emojione does not have any of these yet), http://emojipedia.org/emoji-zwj-sequences/
   // occupationZwj: '\u{1F468}\u{200D}\u{1F393}',
@@ -140,16 +142,25 @@ function generateUnicodeSupportMap(testMap) {
 
 function getUnicodeSupportMap() {
   let unicodeSupportMap;
-  const userAgentFromCache = window.localStorage.getItem('gl-emoji-user-agent');
+  let userAgentFromCache;
+
+  const isLocalStorageAvailable = AccessorUtilities.isLocalStorageAccessSafe();
+
+  if (isLocalStorageAvailable) userAgentFromCache = window.localStorage.getItem('gl-emoji-user-agent');
+
   try {
     unicodeSupportMap = JSON.parse(window.localStorage.getItem('gl-emoji-unicode-support-map'));
   } catch (err) {
     // swallow
   }
+
   if (!unicodeSupportMap || userAgentFromCache !== navigator.userAgent) {
     unicodeSupportMap = generateUnicodeSupportMap(unicodeSupportTestMap);
-    window.localStorage.setItem('gl-emoji-user-agent', navigator.userAgent);
-    window.localStorage.setItem('gl-emoji-unicode-support-map', JSON.stringify(unicodeSupportMap));
+
+    if (isLocalStorageAvailable) {
+      window.localStorage.setItem('gl-emoji-user-agent', navigator.userAgent);
+      window.localStorage.setItem('gl-emoji-unicode-support-map', JSON.stringify(unicodeSupportMap));
+    }
   }
 
   return unicodeSupportMap;
diff --git a/app/assets/javascripts/blob/balsamiq/balsamiq_viewer.js b/app/assets/javascripts/blob/balsamiq/balsamiq_viewer.js
new file mode 100644
index 00000000000..cdbfe36ca1c
--- /dev/null
+++ b/app/assets/javascripts/blob/balsamiq/balsamiq_viewer.js
@@ -0,0 +1,114 @@
+/* global Flash */
+
+import sqljs from 'sql.js';
+import { template as _template } from 'underscore';
+
+const PREVIEW_TEMPLATE = _template(`
+  <div class="panel panel-default">
+    <div class="panel-heading"><%- name %></div>
+    <div class="panel-body">
+      <img class="img-thumbnail" src="data:image/png;base64,<%- image %>"/>
+    </div>
+  </div>
+`);
+
+class BalsamiqViewer {
+  constructor(viewer) {
+    this.viewer = viewer;
+    this.endpoint = this.viewer.dataset.endpoint;
+  }
+
+  loadFile() {
+    const xhr = new XMLHttpRequest();
+
+    xhr.open('GET', this.endpoint, true);
+    xhr.responseType = 'arraybuffer';
+
+    xhr.onload = this.renderFile.bind(this);
+    xhr.onerror = BalsamiqViewer.onError;
+
+    xhr.send();
+  }
+
+  renderFile(loadEvent) {
+    const container = document.createElement('ul');
+
+    this.initDatabase(loadEvent.target.response);
+
+    const previews = this.getPreviews();
+    previews.forEach((preview) => {
+      const renderedPreview = this.renderPreview(preview);
+
+      container.appendChild(renderedPreview);
+    });
+
+    container.classList.add('list-inline');
+    container.classList.add('previews');
+
+    this.viewer.appendChild(container);
+  }
+
+  initDatabase(data) {
+    const previewBinary = new Uint8Array(data);
+
+    this.database = new sqljs.Database(previewBinary);
+  }
+
+  getPreviews() {
+    const thumbnails = this.database.exec('SELECT * FROM thumbnails');
+
+    return thumbnails[0].values.map(BalsamiqViewer.parsePreview);
+  }
+
+  getResource(resourceID) {
+    const resources = this.database.exec(`SELECT * FROM resources WHERE id = '${resourceID}'`);
+
+    return resources[0];
+  }
+
+  renderPreview(preview) {
+    const previewElement = document.createElement('li');
+
+    previewElement.classList.add('preview');
+    previewElement.innerHTML = this.renderTemplate(preview);
+
+    return previewElement;
+  }
+
+  renderTemplate(preview) {
+    const resource = this.getResource(preview.resourceID);
+    const name = BalsamiqViewer.parseTitle(resource);
+    const image = preview.image;
+
+    const template = PREVIEW_TEMPLATE({
+      name,
+      image,
+    });
+
+    return template;
+  }
+
+  static parsePreview(preview) {
+    return JSON.parse(preview[1]);
+  }
+
+  /*
+   * resource = {
+   *   columns: ['ID', 'BRANCHID', 'ATTRIBUTES', 'DATA'],
+   *   values: [['id', 'branchId', 'attributes', 'data']],
+   * }
+   *
+   * 'attributes' being a JSON string containing the `name` property.
+   */
+  static parseTitle(resource) {
+    return JSON.parse(resource.values[0][2]).name;
+  }
+
+  static onError() {
+    const flash = new Flash('Balsamiq file could not be loaded.');
+
+    return flash;
+  }
+}
+
+export default BalsamiqViewer;
diff --git a/app/assets/javascripts/blob/balsamiq_viewer.js b/app/assets/javascripts/blob/balsamiq_viewer.js
new file mode 100644
index 00000000000..1dacf84470f
--- /dev/null
+++ b/app/assets/javascripts/blob/balsamiq_viewer.js
@@ -0,0 +1,6 @@
+import BalsamiqViewer from './balsamiq/balsamiq_viewer';
+
+document.addEventListener('DOMContentLoaded', () => {
+  const balsamiqViewer = new BalsamiqViewer(document.getElementById('js-balsamiq-viewer'));
+  balsamiqViewer.loadFile();
+});
diff --git a/app/assets/javascripts/blob/file_template_mediator.js b/app/assets/javascripts/blob/file_template_mediator.js
index 3062cd51ee3..a20c6ca7a21 100644
--- a/app/assets/javascripts/blob/file_template_mediator.js
+++ b/app/assets/javascripts/blob/file_template_mediator.js
@@ -99,7 +99,7 @@ export default class FileTemplateMediator {
     });
   }
 
-  selectTemplateType(item, el, e) {
+  selectTemplateType(item, e) {
     if (e) {
       e.preventDefault();
     }
@@ -117,6 +117,10 @@ export default class FileTemplateMediator {
     this.cacheToggleText();
   }
 
+  selectTemplateTypeOptions(options) {
+    this.selectTemplateType(options.selectedObj, options.e);
+  }
+
   selectTemplateFile(selector, query, data) {
     selector.renderLoading();
     // in case undo menu is already already there
diff --git a/app/assets/javascripts/blob/file_template_selector.js b/app/assets/javascripts/blob/file_template_selector.js
index 31dd45fac89..ab5b3751c4e 100644
--- a/app/assets/javascripts/blob/file_template_selector.js
+++ b/app/assets/javascripts/blob/file_template_selector.js
@@ -52,9 +52,17 @@ export default class FileTemplateSelector {
       .removeClass('fa-spinner fa-spin');
   }
 
-  reportSelection(query, el, e, data) {
+  reportSelection(options) {
+    const { query, e, data } = options;
     e.preventDefault();
     return this.mediator.selectTemplateFile(this, query, data);
   }
+
+  reportSelectionName(options) {
+    const opts = options;
+    opts.query = options.selectedObj.name;
+
+    this.reportSelection(opts);
+  }
 }
 
diff --git a/app/assets/javascripts/blob/target_branch_dropdown.js b/app/assets/javascripts/blob/target_branch_dropdown.js
index 216f069ef71..d52d69b1274 100644
--- a/app/assets/javascripts/blob/target_branch_dropdown.js
+++ b/app/assets/javascripts/blob/target_branch_dropdown.js
@@ -37,8 +37,8 @@ class TargetBranchDropDown {
         }
         return SELECT_ITEM_MSG;
       },
-      clicked(item, el, e) {
-        e.preventDefault();
+      clicked(options) {
+        options.e.preventDefault();
         self.onClick.call(self);
       },
       fieldName: self.fieldName,
diff --git a/app/assets/javascripts/blob/template_selector.js b/app/assets/javascripts/blob/template_selector.js
index d7c1c32efbd..888883163c5 100644
--- a/app/assets/javascripts/blob/template_selector.js
+++ b/app/assets/javascripts/blob/template_selector.js
@@ -24,7 +24,7 @@ export default class TemplateSelector {
       search: {
         fields: ['name'],
       },
-      clicked: (item, el, e) => this.fetchFileTemplate(item, el, e),
+      clicked: options => this.fetchFileTemplate(options),
       text: item => item.name,
     });
   }
@@ -51,7 +51,10 @@ export default class TemplateSelector {
     return this.$dropdownContainer.removeClass('hidden');
   }
 
-  fetchFileTemplate(item, el, e) {
+  fetchFileTemplate(options) {
+    const { e } = options;
+    const item = options.selectedObj;
+
     e.preventDefault();
     return this.requestFile(item);
   }
diff --git a/app/assets/javascripts/blob/template_selectors/ci_yaml_selector.js b/app/assets/javascripts/blob/template_selectors/ci_yaml_selector.js
index 935df07677c..f2f81af137b 100644
--- a/app/assets/javascripts/blob/template_selectors/ci_yaml_selector.js
+++ b/app/assets/javascripts/blob/template_selectors/ci_yaml_selector.js
@@ -25,7 +25,7 @@ export default class BlobCiYamlSelector extends FileTemplateSelector {
       search: {
         fields: ['name'],
       },
-      clicked: (query, el, e) => this.reportSelection(query.name, el, e),
+      clicked: options => this.reportSelectionName(options),
       text: item => item.name,
     });
   }
diff --git a/app/assets/javascripts/blob/template_selectors/dockerfile_selector.js b/app/assets/javascripts/blob/template_selectors/dockerfile_selector.js
index b4b4d09c315..3cb7b960aaa 100644
--- a/app/assets/javascripts/blob/template_selectors/dockerfile_selector.js
+++ b/app/assets/javascripts/blob/template_selectors/dockerfile_selector.js
@@ -25,7 +25,7 @@ export default class DockerfileSelector extends FileTemplateSelector {
       search: {
         fields: ['name'],
       },
-      clicked: (query, el, e) => this.reportSelection(query.name, el, e),
+      clicked: options => this.reportSelectionName(options),
       text: item => item.name,
     });
   }
diff --git a/app/assets/javascripts/blob/template_selectors/gitignore_selector.js b/app/assets/javascripts/blob/template_selectors/gitignore_selector.js
index aefae54ae71..7efda8e7f50 100644
--- a/app/assets/javascripts/blob/template_selectors/gitignore_selector.js
+++ b/app/assets/javascripts/blob/template_selectors/gitignore_selector.js
@@ -24,7 +24,7 @@ export default class BlobGitignoreSelector extends FileTemplateSelector {
       search: {
         fields: ['name'],
       },
-      clicked: (query, el, e) => this.reportSelection(query.name, el, e),
+      clicked: options => this.reportSelectionName(options),
       text: item => item.name,
     });
   }
diff --git a/app/assets/javascripts/blob/template_selectors/license_selector.js b/app/assets/javascripts/blob/template_selectors/license_selector.js
index c8abd689ab4..1d757332f6c 100644
--- a/app/assets/javascripts/blob/template_selectors/license_selector.js
+++ b/app/assets/javascripts/blob/template_selectors/license_selector.js
@@ -24,13 +24,22 @@ export default class BlobLicenseSelector extends FileTemplateSelector {
       search: {
         fields: ['name'],
       },
-      clicked: (query, el, e) => {
+      clicked: (options) => {
+        const { e } = options;
+        const el = options.$el;
+        const query = options.selectedObj;
+
         const data = {
           project: this.$dropdown.data('project'),
           fullname: this.$dropdown.data('fullname'),
         };
 
-        this.reportSelection(query.id, el, e, data);
+        this.reportSelection({
+          query: query.id,
+          el,
+          e,
+          data,
+        });
       },
       text: item => item.name,
     });
diff --git a/app/assets/javascripts/blob/template_selectors/type_selector.js b/app/assets/javascripts/blob/template_selectors/type_selector.js
index 56f23ef0568..a09381014a7 100644
--- a/app/assets/javascripts/blob/template_selectors/type_selector.js
+++ b/app/assets/javascripts/blob/template_selectors/type_selector.js
@@ -17,7 +17,7 @@ export default class FileTemplateTypeSelector extends FileTemplateSelector {
       filterable: false,
       selectable: true,
       toggleLabel: item => item.name,
-      clicked: (item, el, e) => this.mediator.selectTemplateType(item, el, e),
+      clicked: options => this.mediator.selectTemplateTypeOptions(options),
       text: item => item.name,
     });
   }
diff --git a/app/assets/javascripts/boards/boards_bundle.js b/app/assets/javascripts/boards/boards_bundle.js
index 8c08b2d4db3..88eb4251339 100644
--- a/app/assets/javascripts/boards/boards_bundle.js
+++ b/app/assets/javascripts/boards/boards_bundle.js
@@ -11,7 +11,7 @@ require('./models/issue');
 require('./models/label');
 require('./models/list');
 require('./models/milestone');
-require('./models/user');
+require('./models/assignee');
 require('./stores/boards_store');
 require('./stores/modal_store');
 require('./services/board_service');
diff --git a/app/assets/javascripts/boards/components/board_new_issue.js b/app/assets/javascripts/boards/components/board_new_issue.js
index 0fa85b6fe14..1ce95b62138 100644
--- a/app/assets/javascripts/boards/components/board_new_issue.js
+++ b/app/assets/javascripts/boards/components/board_new_issue.js
@@ -26,6 +26,7 @@ export default {
         title: this.title,
         labels,
         subscribed: true,
+        assignees: [],
       });
 
       this.list.newIssue(issue)
diff --git a/app/assets/javascripts/boards/components/board_sidebar.js b/app/assets/javascripts/boards/components/board_sidebar.js
index f0066d4ec5d..317cef9f227 100644
--- a/app/assets/javascripts/boards/components/board_sidebar.js
+++ b/app/assets/javascripts/boards/components/board_sidebar.js
@@ -3,8 +3,13 @@
 /* global MilestoneSelect */
 /* global LabelsSelect */
 /* global Sidebar */
+/* global Flash */
 
 import Vue from 'vue';
+import eventHub from '../../sidebar/event_hub';
+
+import AssigneeTitle from '../../sidebar/components/assignees/assignee_title';
+import Assignees from '../../sidebar/components/assignees/assignees';
 
 require('./sidebar/remove_issue');
 
@@ -22,6 +27,7 @@ gl.issueBoards.BoardSidebar = Vue.extend({
       detail: Store.detail,
       issue: {},
       list: {},
+      loadingAssignees: false,
     };
   },
   computed: {
@@ -43,6 +49,10 @@ gl.issueBoards.BoardSidebar = Vue.extend({
 
         this.issue = this.detail.issue;
         this.list = this.detail.list;
+
+        this.$nextTick(() => {
+          this.endpoint = this.$refs.assigneeDropdown.dataset.issueUpdate;
+        });
       },
       deep: true
     },
@@ -53,12 +63,57 @@ gl.issueBoards.BoardSidebar = Vue.extend({
           $('.right-sidebar').getNiceScroll().resize();
         });
       }
-    }
+
+      this.issue = this.detail.issue;
+      this.list = this.detail.list;
+    },
+    deep: true
   },
   methods: {
     closeSidebar () {
       this.detail.issue = {};
-    }
+    },
+    assignSelf () {
+      // Notify gl dropdown that we are now assigning to current user
+      this.$refs.assigneeBlock.dispatchEvent(new Event('assignYourself'));
+
+      this.addAssignee(this.currentUser);
+      this.saveAssignees();
+    },
+    removeAssignee (a) {
+      gl.issueBoards.BoardsStore.detail.issue.removeAssignee(a);
+    },
+    addAssignee (a) {
+      gl.issueBoards.BoardsStore.detail.issue.addAssignee(a);
+    },
+    removeAllAssignees () {
+      gl.issueBoards.BoardsStore.detail.issue.removeAllAssignees();
+    },
+    saveAssignees () {
+      this.loadingAssignees = true;
+
+      gl.issueBoards.BoardsStore.detail.issue.update(this.endpoint)
+        .then(() => {
+          this.loadingAssignees = false;
+        })
+        .catch(() => {
+          this.loadingAssignees = false;
+          return new Flash('An error occurred while saving assignees');
+        });
+    },
+  },
+  created () {
+    // Get events from glDropdown
+    eventHub.$on('sidebar.removeAssignee', this.removeAssignee);
+    eventHub.$on('sidebar.addAssignee', this.addAssignee);
+    eventHub.$on('sidebar.removeAllAssignees', this.removeAllAssignees);
+    eventHub.$on('sidebar.saveAssignees', this.saveAssignees);
+  },
+  beforeDestroy() {
+    eventHub.$off('sidebar.removeAssignee', this.removeAssignee);
+    eventHub.$off('sidebar.addAssignee', this.addAssignee);
+    eventHub.$off('sidebar.removeAllAssignees', this.removeAllAssignees);
+    eventHub.$off('sidebar.saveAssignees', this.saveAssignees);
   },
   mounted () {
     new IssuableContext(this.currentUser);
@@ -70,5 +125,7 @@ gl.issueBoards.BoardSidebar = Vue.extend({
   },
   components: {
     removeBtn: gl.issueBoards.RemoveIssueBtn,
+    'assignee-title': AssigneeTitle,
+    assignees: Assignees,
   },
 });
diff --git a/app/assets/javascripts/boards/components/issue_card_inner.js b/app/assets/javascripts/boards/components/issue_card_inner.js
index fc154ee7b8b..710207db0c7 100644
--- a/app/assets/javascripts/boards/components/issue_card_inner.js
+++ b/app/assets/javascripts/boards/components/issue_card_inner.js
@@ -31,18 +31,36 @@ gl.issueBoards.IssueCardInner = Vue.extend({
       default: false,
     },
   },
+  data() {
+    return {
+      limitBeforeCounter: 3,
+      maxRender: 4,
+      maxCounter: 99,
+    };
+  },
   computed: {
-    cardUrl() {
-      return `${this.issueLinkBase}/${this.issue.id}`;
+    numberOverLimit() {
+      return this.issue.assignees.length - this.limitBeforeCounter;
     },
-    assigneeUrl() {
-      return `${this.rootPath}${this.issue.assignee.username}`;
+    assigneeCounterTooltip() {
+      return `${this.assigneeCounterLabel} more`;
+    },
+    assigneeCounterLabel() {
+      if (this.numberOverLimit > this.maxCounter) {
+        return `${this.maxCounter}+`;
+      }
+
+      return `+${this.numberOverLimit}`;
     },
-    assigneeUrlTitle() {
-      return `Assigned to ${this.issue.assignee.name}`;
+    shouldRenderCounter() {
+      if (this.issue.assignees.length <= this.maxRender) {
+        return false;
+      }
+
+      return this.issue.assignees.length > this.numberOverLimit;
     },
-    avatarUrlTitle() {
-      return `Avatar for ${this.issue.assignee.name}`;
+    cardUrl() {
+      return `${this.issueLinkBase}/${this.issue.id}`;
     },
     issueId() {
       return `#${this.issue.id}`;
@@ -52,6 +70,28 @@ gl.issueBoards.IssueCardInner = Vue.extend({
     },
   },
   methods: {
+    isIndexLessThanlimit(index) {
+      return index < this.limitBeforeCounter;
+    },
+    shouldRenderAssignee(index) {
+      // Eg. maxRender is 4,
+      // Render up to all 4 assignees if there are only 4 assigness
+      // Otherwise render up to the limitBeforeCounter
+      if (this.issue.assignees.length <= this.maxRender) {
+        return index < this.maxRender;
+      }
+
+      return index < this.limitBeforeCounter;
+    },
+    assigneeUrl(assignee) {
+      return `${this.rootPath}${assignee.username}`;
+    },
+    assigneeUrlTitle(assignee) {
+      return `Assigned to ${assignee.name}`;
+    },
+    avatarUrlTitle(assignee) {
+      return `Avatar for ${assignee.name}`;
+    },
     showLabel(label) {
       if (!this.list) return true;
 
@@ -105,25 +145,39 @@ gl.issueBoards.IssueCardInner = Vue.extend({
             {{ issueId }}
           </span>
         </h4>
-        <a
-          class="card-assignee has-tooltip js-no-trigger"
-          :href="assigneeUrl"
-          :title="assigneeUrlTitle"
-          v-if="issue.assignee"
-          data-container="body"
-        >
-          <img
-            class="avatar avatar-inline s20 js-no-trigger"
-            :src="issue.assignee.avatar"
-            width="20"
-            height="20"
-            :alt="avatarUrlTitle"
-          />
-        </a>
+        <div class="card-assignee">
+          <a
+            class="has-tooltip js-no-trigger"
+            :href="assigneeUrl(assignee)"
+            :title="assigneeUrlTitle(assignee)"
+            v-for="(assignee, index) in issue.assignees"
+            v-if="shouldRenderAssignee(index)"
+            data-container="body"
+            data-placement="bottom"
+          >
+            <img
+              class="avatar avatar-inline s20"
+              :src="assignee.avatar"
+              width="20"
+              height="20"
+              :alt="avatarUrlTitle(assignee)"
+            />
+          </a>
+          <span
+            class="avatar-counter has-tooltip"
+            :title="assigneeCounterTooltip"
+            v-if="shouldRenderCounter"
+          >
+           {{ assigneeCounterLabel }}
+          </span>
+        </div>
       </div>
-      <div class="card-footer" v-if="showLabelFooter">
+      <div
+        class="card-footer"
+        v-if="showLabelFooter"
+      >
         <button
-          class="label color-label has-tooltip js-no-trigger"
+          class="label color-label has-tooltip"
           v-for="label in issue.labels"
           type="button"
           v-if="showLabel(label)"
diff --git a/app/assets/javascripts/boards/components/new_list_dropdown.js b/app/assets/javascripts/boards/components/new_list_dropdown.js
index 7e3bb79af1d..f29b6caa1ac 100644
--- a/app/assets/javascripts/boards/components/new_list_dropdown.js
+++ b/app/assets/javascripts/boards/components/new_list_dropdown.js
@@ -52,7 +52,9 @@ gl.issueBoards.newListDropdownInit = () => {
       filterable: true,
       selectable: true,
       multiSelect: true,
-      clicked (label, $el, e) {
+      clicked (options) {
+        const { e } = options;
+        const label = options.selectedObj;
         e.preventDefault();
 
         if (!Store.findList('title', label.title)) {
diff --git a/app/assets/javascripts/boards/models/user.js b/app/assets/javascripts/boards/models/assignee.js
index 2af583c3279..05dd449e4fd 100644
--- a/app/assets/javascripts/boards/models/user.js
+++ b/app/assets/javascripts/boards/models/assignee.js
@@ -1,4 +1,6 @@
-class ListUser {
+/* eslint-disable no-unused-vars */
+
+class ListAssignee {
   constructor(user, defaultAvatar) {
     this.id = user.id;
     this.name = user.name;
@@ -7,4 +9,4 @@ class ListUser {
   }
 }
 
-window.ListUser = ListUser;
+window.ListAssignee = ListAssignee;
diff --git a/app/assets/javascripts/boards/models/issue.js b/app/assets/javascripts/boards/models/issue.js
index db783467f87..6c2d8a3781b 100644
--- a/app/assets/javascripts/boards/models/issue.js
+++ b/app/assets/javascripts/boards/models/issue.js
@@ -1,7 +1,7 @@
 /* eslint-disable no-unused-vars, space-before-function-paren, arrow-body-style, arrow-parens, comma-dangle, max-len */
 /* global ListLabel */
 /* global ListMilestone */
-/* global ListUser */
+/* global ListAssignee */
 
 import Vue from 'vue';
 
@@ -14,14 +14,10 @@ class ListIssue {
     this.dueDate = obj.due_date;
     this.subscribed = obj.subscribed;
     this.labels = [];
+    this.assignees = [];
     this.selected = false;
-    this.assignee = false;
     this.position = obj.relative_position || Infinity;
 
-    if (obj.assignee) {
-      this.assignee = new ListUser(obj.assignee, defaultAvatar);
-    }
-
     if (obj.milestone) {
       this.milestone = new ListMilestone(obj.milestone);
     }
@@ -29,6 +25,8 @@ class ListIssue {
     obj.labels.forEach((label) => {
       this.labels.push(new ListLabel(label));
     });
+
+    this.assignees = obj.assignees.map(a => new ListAssignee(a, defaultAvatar));
   }
 
   addLabel (label) {
@@ -51,6 +49,26 @@ class ListIssue {
     labels.forEach(this.removeLabel.bind(this));
   }
 
+  addAssignee (assignee) {
+    if (!this.findAssignee(assignee)) {
+      this.assignees.push(new ListAssignee(assignee));
+    }
+  }
+
+  findAssignee (findAssignee) {
+    return this.assignees.filter(assignee => assignee.id === findAssignee.id)[0];
+  }
+
+  removeAssignee (removeAssignee) {
+    if (removeAssignee) {
+      this.assignees = this.assignees.filter(assignee => assignee.id !== removeAssignee.id);
+    }
+  }
+
+  removeAllAssignees () {
+    this.assignees = [];
+  }
+
   getLists () {
     return gl.issueBoards.BoardsStore.state.lists.filter(list => list.findIssue(this.id));
   }
@@ -60,7 +78,7 @@ class ListIssue {
       issue: {
         milestone_id: this.milestone ? this.milestone.id : null,
         due_date: this.dueDate,
-        assignee_id: this.assignee ? this.assignee.id : null,
+        assignee_ids: this.assignees.length > 0 ? this.assignees.map((u) => u.id) : [0],
         label_ids: this.labels.map((label) => label.id)
       }
     };
diff --git a/app/assets/javascripts/dispatcher.js b/app/assets/javascripts/dispatcher.js
index b87c57c38fe..b16ff2a0221 100644
--- a/app/assets/javascripts/dispatcher.js
+++ b/app/assets/javascripts/dispatcher.js
@@ -252,6 +252,7 @@ const ShortcutsBlob = require('./shortcuts_blob');
           }
           break;
         case 'projects:pipelines:builds':
+        case 'projects:pipelines:failures':
         case 'projects:pipelines:show':
           const { controllerAction } = document.querySelector('.js-pipeline-container').dataset;
           const pipelineStatusUrl = `${document.querySelector('.js-pipeline-tab-link a').getAttribute('href')}/status.json`;
diff --git a/app/assets/javascripts/filtered_search/components/recent_searches_dropdown_content.js b/app/assets/javascripts/filtered_search/components/recent_searches_dropdown_content.js
index 9126422b335..15052dbd362 100644
--- a/app/assets/javascripts/filtered_search/components/recent_searches_dropdown_content.js
+++ b/app/assets/javascripts/filtered_search/components/recent_searches_dropdown_content.js
@@ -8,6 +8,11 @@ export default {
       type: Array,
       required: true,
     },
+    isLocalStorageAvailable: {
+      type: Boolean,
+      required: false,
+      default: true,
+    },
   },
 
   computed: {
@@ -47,7 +52,12 @@ export default {
 
   template: `
     <div>
-      <ul v-if="hasItems">
+      <div
+        v-if="!isLocalStorageAvailable"
+        class="dropdown-info-note">
+        This feature requires local storage to be enabled
+      </div>
+      <ul v-else-if="hasItems">
         <li
           v-for="(item, index) in processedItems"
           :key="index">
diff --git a/app/assets/javascripts/filtered_search/filtered_search_manager.js b/app/assets/javascripts/filtered_search/filtered_search_manager.js
index 36af0674ac6..9fea563370f 100644
--- a/app/assets/javascripts/filtered_search/filtered_search_manager.js
+++ b/app/assets/javascripts/filtered_search/filtered_search_manager.js
@@ -1,5 +1,3 @@
-/* global Flash */
-
 import FilteredSearchContainer from './container';
 import RecentSearchesRoot from './recent_searches_root';
 import RecentSearchesStore from './stores/recent_searches_store';
@@ -15,7 +13,9 @@ class FilteredSearchManager {
     this.tokensContainer = this.container.querySelector('.tokens-container');
     this.filteredSearchTokenKeys = gl.FilteredSearchTokenKeys;
 
-    this.recentSearchesStore = new RecentSearchesStore();
+    this.recentSearchesStore = new RecentSearchesStore({
+      isLocalStorageAvailable: RecentSearchesService.isAvailable(),
+    });
     let recentSearchesKey = 'issue-recent-searches';
     if (page === 'merge_requests') {
       recentSearchesKey = 'merge-request-recent-searches';
@@ -24,9 +24,10 @@ class FilteredSearchManager {
 
     // Fetch recent searches from localStorage
     this.fetchingRecentSearchesPromise = this.recentSearchesService.fetch()
-      .catch(() => {
+      .catch((error) => {
+        if (error.name === 'RecentSearchesServiceError') return undefined;
         // eslint-disable-next-line no-new
-        new Flash('An error occured while parsing recent searches');
+        new window.Flash('An error occured while parsing recent searches');
         // Gracefully fail to empty array
         return [];
       })
diff --git a/app/assets/javascripts/filtered_search/filtered_search_visual_tokens.js b/app/assets/javascripts/filtered_search/filtered_search_visual_tokens.js
index 453ecccc6fc..f3003b86493 100644
--- a/app/assets/javascripts/filtered_search/filtered_search_visual_tokens.js
+++ b/app/assets/javascripts/filtered_search/filtered_search_visual_tokens.js
@@ -1,3 +1,5 @@
+import AjaxCache from '~/lib/utils/ajax_cache';
+import '~/flash'; /* global Flash */
 import FilteredSearchContainer from './container';
 
 class FilteredSearchVisualTokens {
@@ -48,6 +50,40 @@ class FilteredSearchVisualTokens {
     `;
   }
 
+  static updateLabelTokenColor(tokenValueContainer, tokenValue) {
+    const filteredSearchInput = FilteredSearchContainer.container.querySelector('.filtered-search');
+    const baseEndpoint = filteredSearchInput.dataset.baseEndpoint;
+    const labelsEndpoint = `${baseEndpoint}/labels.json`;
+
+    return AjaxCache.retrieve(labelsEndpoint)
+    .then((labels) => {
+      const matchingLabel = (labels || []).find(label => `~${gl.DropdownUtils.getEscapedText(label.title)}` === tokenValue);
+
+      if (!matchingLabel) {
+        return;
+      }
+
+      const tokenValueStyle = tokenValueContainer.style;
+      tokenValueStyle.backgroundColor = matchingLabel.color;
+      tokenValueStyle.color = matchingLabel.text_color;
+
+      if (matchingLabel.text_color === '#FFFFFF') {
+        const removeToken = tokenValueContainer.querySelector('.remove-token');
+        removeToken.classList.add('inverted');
+      }
+    })
+    .catch(() => new Flash('An error occurred while fetching label colors.'));
+  }
+
+  static renderVisualTokenValue(parentElement, tokenName, tokenValue) {
+    const tokenValueContainer = parentElement.querySelector('.value-container');
+    tokenValueContainer.querySelector('.value').innerText = tokenValue;
+
+    if (tokenName.toLowerCase() === 'label') {
+      FilteredSearchVisualTokens.updateLabelTokenColor(tokenValueContainer, tokenValue);
+    }
+  }
+
   static addVisualTokenElement(name, value, isSearchTerm) {
     const li = document.createElement('li');
     li.classList.add('js-visual-token');
@@ -55,7 +91,7 @@ class FilteredSearchVisualTokens {
 
     if (value) {
       li.innerHTML = FilteredSearchVisualTokens.createVisualTokenElementHTML();
-      li.querySelector('.value').innerText = value;
+      FilteredSearchVisualTokens.renderVisualTokenValue(li, name, value);
     } else {
       li.innerHTML = '<div class="name"></div>';
     }
@@ -74,7 +110,7 @@ class FilteredSearchVisualTokens {
       const name = FilteredSearchVisualTokens.getLastTokenPartial();
       lastVisualToken.innerHTML = FilteredSearchVisualTokens.createVisualTokenElementHTML();
       lastVisualToken.querySelector('.name').innerText = name;
-      lastVisualToken.querySelector('.value').innerText = value;
+      FilteredSearchVisualTokens.renderVisualTokenValue(lastVisualToken, name, value);
     }
   }
 
@@ -183,6 +219,9 @@ class FilteredSearchVisualTokens {
 
   static moveInputToTheRight() {
     const input = FilteredSearchContainer.container.querySelector('.filtered-search');
+
+    if (!input) return;
+
     const inputLi = input.parentElement;
     const tokenContainer = FilteredSearchContainer.container.querySelector('.tokens-container');
 
diff --git a/app/assets/javascripts/filtered_search/recent_searches_root.js b/app/assets/javascripts/filtered_search/recent_searches_root.js
index 4e38409e12a..b2e6f63aacf 100644
--- a/app/assets/javascripts/filtered_search/recent_searches_root.js
+++ b/app/assets/javascripts/filtered_search/recent_searches_root.js
@@ -29,12 +29,15 @@ class RecentSearchesRoot {
   }
 
   render() {
+    const state = this.store.state;
     this.vm = new Vue({
       el: this.wrapperElement,
-      data: this.store.state,
+      data() { return state; },
       template: `
         <recent-searches-dropdown-content
-          :items="recentSearches" />
+          :items="recentSearches"
+          :is-local-storage-available="isLocalStorageAvailable"
+          />
       `,
       components: {
         'recent-searches-dropdown-content': RecentSearchesDropdownContent,
diff --git a/app/assets/javascripts/filtered_search/services/recent_searches_service.js b/app/assets/javascripts/filtered_search/services/recent_searches_service.js
index 3e402d5aed0..a056dea928d 100644
--- a/app/assets/javascripts/filtered_search/services/recent_searches_service.js
+++ b/app/assets/javascripts/filtered_search/services/recent_searches_service.js
@@ -1,9 +1,17 @@
+import RecentSearchesServiceError from './recent_searches_service_error';
+import AccessorUtilities from '../../lib/utils/accessor';
+
 class RecentSearchesService {
   constructor(localStorageKey = 'issuable-recent-searches') {
     this.localStorageKey = localStorageKey;
   }
 
   fetch() {
+    if (!RecentSearchesService.isAvailable()) {
+      const error = new RecentSearchesServiceError();
+      return Promise.reject(error);
+    }
+
     const input = window.localStorage.getItem(this.localStorageKey);
 
     let searches = [];
@@ -19,8 +27,14 @@ class RecentSearchesService {
   }
 
   save(searches = []) {
+    if (!RecentSearchesService.isAvailable()) return;
+
     window.localStorage.setItem(this.localStorageKey, JSON.stringify(searches));
   }
+
+  static isAvailable() {
+    return AccessorUtilities.isLocalStorageAccessSafe();
+  }
 }
 
 export default RecentSearchesService;
diff --git a/app/assets/javascripts/filtered_search/services/recent_searches_service_error.js b/app/assets/javascripts/filtered_search/services/recent_searches_service_error.js
new file mode 100644
index 00000000000..5917b223d63
--- /dev/null
+++ b/app/assets/javascripts/filtered_search/services/recent_searches_service_error.js
@@ -0,0 +1,11 @@
+class RecentSearchesServiceError {
+  constructor(message) {
+    this.name = 'RecentSearchesServiceError';
+    this.message = message || 'Recent Searches Service is unavailable';
+  }
+}
+
+// Can't use `extends` for builtin prototypes and get true inheritance yet
+RecentSearchesServiceError.prototype = Error.prototype;
+
+export default RecentSearchesServiceError;
diff --git a/app/assets/javascripts/gl_dropdown.js b/app/assets/javascripts/gl_dropdown.js
index 689a6b3f856..7d30f9207e9 100644
--- a/app/assets/javascripts/gl_dropdown.js
+++ b/app/assets/javascripts/gl_dropdown.js
@@ -256,7 +256,8 @@ GitLabDropdown = (function() {
               }
             };
           // Remote data
-          })(this)
+          })(this),
+          instance: this,
         });
       }
     }
@@ -270,6 +271,7 @@ GitLabDropdown = (function() {
         remote: this.options.filterRemote,
         query: this.options.data,
         keys: searchFields,
+        instance: this,
         elements: (function(_this) {
           return function() {
             selector = '.dropdown-content li:not(' + NON_SELECTABLE_CLASSES + ')';
@@ -344,21 +346,26 @@ GitLabDropdown = (function() {
       }
       this.dropdown.on("click", selector, function(e) {
         var $el, selected, selectedObj, isMarking;
-        $el = $(this);
+        $el = $(e.currentTarget);
         selected = self.rowClicked($el);
         selectedObj = selected ? selected[0] : null;
         isMarking = selected ? selected[1] : null;
-        if (self.options.clicked) {
-          self.options.clicked(selectedObj, $el, e, isMarking);
+        if (this.options.clicked) {
+          this.options.clicked.call(this, {
+            selectedObj,
+            $el,
+            e,
+            isMarking,
+          });
         }
 
         // Update label right after all modifications in dropdown has been done
-        if (self.options.toggleLabel) {
-          self.updateLabel(selectedObj, $el, self);
+        if (this.options.toggleLabel) {
+          this.updateLabel(selectedObj, $el, this);
         }
 
         $el.trigger('blur');
-      });
+      }.bind(this));
     }
   }
 
@@ -440,15 +447,34 @@ GitLabDropdown = (function() {
     }
   };
 
+  GitLabDropdown.prototype.filteredFullData = function() {
+    return this.fullData.filter(r => typeof r === 'object'
+      && !Object.prototype.hasOwnProperty.call(r, 'beforeDivider')
+      && !Object.prototype.hasOwnProperty.call(r, 'header')
+    );
+  };
+
   GitLabDropdown.prototype.opened = function(e) {
     var contentHtml;
     this.resetRows();
     this.addArrowKeyEvent();
 
+    const dropdownToggle = this.dropdown.find('.dropdown-menu-toggle');
+    const hasFilterBulkUpdate = dropdownToggle.hasClass('js-filter-bulk-update');
+    const hasMultiSelect = dropdownToggle.hasClass('js-multiselect');
+
     // Makes indeterminate items effective
-    if (this.fullData && this.dropdown.find('.dropdown-menu-toggle').hasClass('js-filter-bulk-update')) {
+    if (this.fullData && hasFilterBulkUpdate) {
       this.parseData(this.fullData);
     }
+
+    // Process the data to make sure rendered data
+    // matches the correct layout
+    if (this.fullData && hasMultiSelect && this.options.processData) {
+      const inputValue = this.filterInput.val();
+      this.options.processData.call(this.options, inputValue, this.filteredFullData(), this.parseData.bind(this));
+    }
+
     contentHtml = $('.dropdown-content', this.dropdown).html();
     if (this.remote && contentHtml === "") {
       this.remote.execute();
@@ -710,6 +736,11 @@ GitLabDropdown = (function() {
     if (this.options.inputId != null) {
       $input.attr('id', this.options.inputId);
     }
+
+    if (this.options.inputMeta) {
+      $input.attr('data-meta', selectedObject[this.options.inputMeta]);
+    }
+
     return this.dropdown.before($input);
   };
 
@@ -830,7 +861,14 @@ GitLabDropdown = (function() {
     if (instance == null) {
       instance = null;
     }
-    return $(this.el).find(".dropdown-toggle-text").text(this.options.toggleLabel(selected, el, instance));
+
+    let toggleText = this.options.toggleLabel(selected, el, instance);
+    if (this.options.updateLabel) {
+      // Option to override the dropdown label text
+      toggleText = this.options.updateLabel;
+    }
+
+    return $(this.el).find(".dropdown-toggle-text").text(toggleText);
   };
 
   GitLabDropdown.prototype.clearField = function(field, isInput) {
diff --git a/app/assets/javascripts/issuable/issuable_bundle.js b/app/assets/javascripts/issuable/issuable_bundle.js
deleted file mode 100644
index e927cc0077c..00000000000
--- a/app/assets/javascripts/issuable/issuable_bundle.js
+++ /dev/null
@@ -1 +0,0 @@
-require('./time_tracking/time_tracking_bundle');
diff --git a/app/assets/javascripts/issuable/time_tracking/components/collapsed_state.js b/app/assets/javascripts/issuable/time_tracking/components/collapsed_state.js
deleted file mode 100644
index aec13e78f42..00000000000
--- a/app/assets/javascripts/issuable/time_tracking/components/collapsed_state.js
+++ /dev/null
@@ -1,42 +0,0 @@
-import Vue from 'vue';
-import stopwatchSvg from 'icons/_icon_stopwatch.svg';
-
-require('../../../lib/utils/pretty_time');
-
-(() => {
-  Vue.component('time-tracking-collapsed-state', {
-    name: 'time-tracking-collapsed-state',
-    props: [
-      'showComparisonState',
-      'showSpentOnlyState',
-      'showEstimateOnlyState',
-      'showNoTimeTrackingState',
-      'timeSpentHumanReadable',
-      'timeEstimateHumanReadable',
-    ],
-    methods: {
-      abbreviateTime(timeStr) {
-        return gl.utils.prettyTime.abbreviateTime(timeStr);
-      },
-    },
-    template: `
-      <div class='sidebar-collapsed-icon'>
-        ${stopwatchSvg}
-        <div class='time-tracking-collapsed-summary'>
-          <div class='compare' v-if='showComparisonState'>
-            <span>{{ abbreviateTime(timeSpentHumanReadable) }} / {{ abbreviateTime(timeEstimateHumanReadable) }}</span>
-          </div>
-          <div class='estimate-only' v-if='showEstimateOnlyState'>
-            <span class='bold'>-- / {{ abbreviateTime(timeEstimateHumanReadable) }}</span>
-          </div>
-          <div class='spend-only' v-if='showSpentOnlyState'>
-            <span class='bold'>{{ abbreviateTime(timeSpentHumanReadable) }} / --</span>
-          </div>
-          <div class='no-tracking' v-if='showNoTimeTrackingState'>
-            <span class='no-value'>None</span>
-          </div>
-        </div>
-      </div>
-      `,
-  });
-})();
diff --git a/app/assets/javascripts/issuable/time_tracking/components/comparison_pane.js b/app/assets/javascripts/issuable/time_tracking/components/comparison_pane.js
deleted file mode 100644
index c55e263f6f4..00000000000
--- a/app/assets/javascripts/issuable/time_tracking/components/comparison_pane.js
+++ /dev/null
@@ -1,70 +0,0 @@
-import Vue from 'vue';
-
-require('../../../lib/utils/pretty_time');
-
-(() => {
-  const prettyTime = gl.utils.prettyTime;
-
-  Vue.component('time-tracking-comparison-pane', {
-    name: 'time-tracking-comparison-pane',
-    props: [
-      'timeSpent',
-      'timeEstimate',
-      'timeSpentHumanReadable',
-      'timeEstimateHumanReadable',
-    ],
-    computed: {
-      parsedRemaining() {
-        const diffSeconds = this.timeEstimate - this.timeSpent;
-        return prettyTime.parseSeconds(diffSeconds);
-      },
-      timeRemainingHumanReadable() {
-        return prettyTime.stringifyTime(this.parsedRemaining);
-      },
-      timeRemainingTooltip() {
-        const prefix = this.timeRemainingMinutes < 0 ? 'Over by' : 'Time remaining:';
-        return `${prefix} ${this.timeRemainingHumanReadable}`;
-      },
-      /* Diff values for comparison meter */
-      timeRemainingMinutes() {
-        return this.timeEstimate - this.timeSpent;
-      },
-      timeRemainingPercent() {
-        return `${Math.floor((this.timeSpent / this.timeEstimate) * 100)}%`;
-      },
-      timeRemainingStatusClass() {
-        return this.timeEstimate >= this.timeSpent ? 'within_estimate' : 'over_estimate';
-      },
-      /* Parsed time values */
-      parsedEstimate() {
-        return prettyTime.parseSeconds(this.timeEstimate);
-      },
-      parsedSpent() {
-        return prettyTime.parseSeconds(this.timeSpent);
-      },
-    },
-    template: `
-      <div class='time-tracking-comparison-pane'>
-        <div class='compare-meter' data-toggle='tooltip' data-placement='top' role='timeRemainingDisplay'
-          :aria-valuenow='timeRemainingTooltip'
-          :title='timeRemainingTooltip'
-          :data-original-title='timeRemainingTooltip'
-          :class='timeRemainingStatusClass'>
-          <div class='meter-container' role='timeSpentPercent' :aria-valuenow='timeRemainingPercent'>
-            <div :style='{ width: timeRemainingPercent }' class='meter-fill'></div>
-          </div>
-          <div class='compare-display-container'>
-            <div class='compare-display pull-left'>
-              <span class='compare-label'>Spent</span>
-              <span class='compare-value spent'>{{ timeSpentHumanReadable }}</span>
-            </div>
-            <div class='compare-display estimated pull-right'>
-              <span class='compare-label'>Est</span>
-              <span class='compare-value'>{{ timeEstimateHumanReadable }}</span>
-            </div>
-          </div>
-        </div>
-      </div>
-    `,
-  });
-})();
diff --git a/app/assets/javascripts/issuable/time_tracking/components/estimate_only_pane.js b/app/assets/javascripts/issuable/time_tracking/components/estimate_only_pane.js
deleted file mode 100644
index a7fbd704c40..00000000000
--- a/app/assets/javascripts/issuable/time_tracking/components/estimate_only_pane.js
+++ /dev/null
@@ -1,14 +0,0 @@
-import Vue from 'vue';
-
-(() => {
-  Vue.component('time-tracking-estimate-only-pane', {
-    name: 'time-tracking-estimate-only-pane',
-    props: ['timeEstimateHumanReadable'],
-    template: `
-      <div class='time-tracking-estimate-only-pane'>
-        <span class='bold'>Estimated:</span>
-        {{ timeEstimateHumanReadable }}
-      </div>
-    `,
-  });
-})();
diff --git a/app/assets/javascripts/issuable/time_tracking/components/help_state.js b/app/assets/javascripts/issuable/time_tracking/components/help_state.js
deleted file mode 100644
index 344b29ebea4..00000000000
--- a/app/assets/javascripts/issuable/time_tracking/components/help_state.js
+++ /dev/null
@@ -1,25 +0,0 @@
-import Vue from 'vue';
-
-(() => {
-  Vue.component('time-tracking-help-state', {
-    name: 'time-tracking-help-state',
-    props: ['docsUrl'],
-    template: `
-      <div class='time-tracking-help-state'>
-        <div class='time-tracking-info'>
-          <h4>Track time with slash commands</h4>
-          <p>Slash commands can be used in the issues description and comment boxes.</p>
-          <p>
-            <code>/estimate</code>
-            will update the estimated time with the latest command.
-          </p>
-          <p>
-            <code>/spend</code>
-            will update the sum of the time spent.
-          </p>
-          <a class='btn btn-default learn-more-button' :href='docsUrl'>Learn more</a>
-        </div>
-      </div>
-    `,
-  });
-})();
diff --git a/app/assets/javascripts/issuable/time_tracking/components/no_tracking_pane.js b/app/assets/javascripts/issuable/time_tracking/components/no_tracking_pane.js
deleted file mode 100644
index b081adf5e64..00000000000
--- a/app/assets/javascripts/issuable/time_tracking/components/no_tracking_pane.js
+++ /dev/null
@@ -1,12 +0,0 @@
-import Vue from 'vue';
-
-(() => {
-  Vue.component('time-tracking-no-tracking-pane', {
-    name: 'time-tracking-no-tracking-pane',
-    template: `
-      <div class='time-tracking-no-tracking-pane'>
-        <span class='no-value'>No estimate or time spent</span>
-      </div>
-    `,
-  });
-})();
diff --git a/app/assets/javascripts/issuable/time_tracking/components/spent_only_pane.js b/app/assets/javascripts/issuable/time_tracking/components/spent_only_pane.js
deleted file mode 100644
index edb9169112f..00000000000
--- a/app/assets/javascripts/issuable/time_tracking/components/spent_only_pane.js
+++ /dev/null
@@ -1,14 +0,0 @@
-import Vue from 'vue';
-
-(() => {
-  Vue.component('time-tracking-spent-only-pane', {
-    name: 'time-tracking-spent-only-pane',
-    props: ['timeSpentHumanReadable'],
-    template: `
-      <div class='time-tracking-spend-only-pane'>
-        <span class='bold'>Spent:</span>
-        {{ timeSpentHumanReadable }}
-      </div>
-    `,
-  });
-})();
diff --git a/app/assets/javascripts/issuable/time_tracking/components/time_tracker.js b/app/assets/javascripts/issuable/time_tracking/components/time_tracker.js
deleted file mode 100644
index 0213522f551..00000000000
--- a/app/assets/javascripts/issuable/time_tracking/components/time_tracker.js
+++ /dev/null
@@ -1,117 +0,0 @@
-import Vue from 'vue';
-
-require('./help_state');
-require('./collapsed_state');
-require('./spent_only_pane');
-require('./no_tracking_pane');
-require('./estimate_only_pane');
-require('./comparison_pane');
-
-(() => {
-  Vue.component('issuable-time-tracker', {
-    name: 'issuable-time-tracker',
-    props: [
-      'time_estimate',
-      'time_spent',
-      'human_time_estimate',
-      'human_time_spent',
-      'docsUrl',
-    ],
-    data() {
-      return {
-        showHelp: false,
-      };
-    },
-    computed: {
-      timeSpent() {
-        return this.time_spent;
-      },
-      timeEstimate() {
-        return this.time_estimate;
-      },
-      timeEstimateHumanReadable() {
-        return this.human_time_estimate;
-      },
-      timeSpentHumanReadable() {
-        return this.human_time_spent;
-      },
-      hasTimeSpent() {
-        return !!this.timeSpent;
-      },
-      hasTimeEstimate() {
-        return !!this.timeEstimate;
-      },
-      showComparisonState() {
-        return this.hasTimeEstimate && this.hasTimeSpent;
-      },
-      showEstimateOnlyState() {
-        return this.hasTimeEstimate && !this.hasTimeSpent;
-      },
-      showSpentOnlyState() {
-        return this.hasTimeSpent && !this.hasTimeEstimate;
-      },
-      showNoTimeTrackingState() {
-        return !this.hasTimeEstimate && !this.hasTimeSpent;
-      },
-      showHelpState() {
-        return !!this.showHelp;
-      },
-    },
-    methods: {
-      toggleHelpState(show) {
-        this.showHelp = show;
-      },
-    },
-    template: `
-      <div class='time_tracker time-tracking-component-wrap' v-cloak>
-        <time-tracking-collapsed-state
-          :show-comparison-state='showComparisonState'
-          :show-help-state='showHelpState'
-          :show-spent-only-state='showSpentOnlyState'
-          :show-estimate-only-state='showEstimateOnlyState'
-          :time-spent-human-readable='timeSpentHumanReadable'
-          :time-estimate-human-readable='timeEstimateHumanReadable'>
-        </time-tracking-collapsed-state>
-        <div class='title hide-collapsed'>
-          Time tracking
-          <div class='help-button pull-right'
-            v-if='!showHelpState'
-            @click='toggleHelpState(true)'>
-            <i class='fa fa-question-circle' aria-hidden='true'></i>
-          </div>
-          <div class='close-help-button pull-right'
-            v-if='showHelpState'
-            @click='toggleHelpState(false)'>
-            <i class='fa fa-close' aria-hidden='true'></i>
-          </div>
-        </div>
-        <div class='time-tracking-content hide-collapsed'>
-          <time-tracking-estimate-only-pane
-            v-if='showEstimateOnlyState'
-            :time-estimate-human-readable='timeEstimateHumanReadable'>
-          </time-tracking-estimate-only-pane>
-          <time-tracking-spent-only-pane
-            v-if='showSpentOnlyState'
-            :time-spent-human-readable='timeSpentHumanReadable'>
-          </time-tracking-spent-only-pane>
-          <time-tracking-no-tracking-pane
-            v-if='showNoTimeTrackingState'>
-          </time-tracking-no-tracking-pane>
-          <time-tracking-comparison-pane
-            v-if='showComparisonState'
-            :time-estimate='timeEstimate'
-            :time-spent='timeSpent'
-            :time-spent-human-readable='timeSpentHumanReadable'
-            :time-estimate-human-readable='timeEstimateHumanReadable'>
-          </time-tracking-comparison-pane>
-          <transition name='help-state-toggle'>
-            <time-tracking-help-state
-              v-if='showHelpState'
-              :docs-url='docsUrl'>
-            </time-tracking-help-state>
-          </transition>
-        </div>
-      </div>
-    `,
-  });
-})();
diff --git a/app/assets/javascripts/issuable/time_tracking/time_tracking_bundle.js b/app/assets/javascripts/issuable/time_tracking/time_tracking_bundle.js
deleted file mode 100644
index 1689a69e1ed..00000000000
--- a/app/assets/javascripts/issuable/time_tracking/time_tracking_bundle.js
+++ /dev/null
@@ -1,66 +0,0 @@
-import Vue from 'vue';
-import VueResource from 'vue-resource';
-
-require('./components/time_tracker');
-require('../../smart_interval');
-require('../../subbable_resource');
-
-Vue.use(VueResource);
-
-(() => {
-  /* This Vue instance represents what will become the parent instance for the
-    * sidebar. It will be responsible for managing `issuable` state and propagating
-    * changes to sidebar components. We will want to create a separate service to
-    * interface with the server at that point.
-   */
-
-  class IssuableTimeTracking {
-    constructor(issuableJSON) {
-      const parsedIssuable = JSON.parse(issuableJSON);
-      return this.initComponent(parsedIssuable);
-    }
-
-    initComponent(parsedIssuable) {
-      this.parentInstance = new Vue({
-        el: '#issuable-time-tracker',
-        data: {
-          issuable: parsedIssuable,
-        },
-        methods: {
-          fetchIssuable() {
-            return gl.IssuableResource.get.call(gl.IssuableResource, {
-              type: 'GET',
-              url: gl.IssuableResource.endpoint,
-            });
-          },
-          updateState(data) {
-            this.issuable = data;
-          },
-          subscribeToUpdates() {
-            gl.IssuableResource.subscribe(data => this.updateState(data));
-          },
-          listenForSlashCommands() {
-            $(document).on('ajax:success', '.gfm-form', (e, data) => {
-              const subscribedCommands = ['spend_time', 'time_estimate'];
-              const changedCommands = data.commands_changes
-                ? Object.keys(data.commands_changes)
-                : [];
-              if (changedCommands && _.intersection(subscribedCommands, changedCommands).length) {
-                this.fetchIssuable();
-              }
-            });
-          },
-        },
-        created() {
-          this.fetchIssuable();
-        },
-        mounted() {
-          this.subscribeToUpdates();
-          this.listenForSlashCommands();
-        },
-      });
-    }
-  }
-
-  gl.IssuableTimeTracking = IssuableTimeTracking;
-})(window.gl || (window.gl = {}));
diff --git a/app/assets/javascripts/issue_show/actions/tasks.js b/app/assets/javascripts/issue_show/actions/tasks.js
new file mode 100644
index 00000000000..0740a9f559c
--- /dev/null
+++ b/app/assets/javascripts/issue_show/actions/tasks.js
@@ -0,0 +1,27 @@
+export default (newStateData, tasks) => {
+  const $tasks = $('#task_status');
+  const $tasksShort = $('#task_status_short');
+  const $issueableHeader = $('.issuable-header');
+  const tasksStates = { newState: null, currentState: null };
+
+  if ($tasks.length === 0) {
+    if (!(newStateData.task_status.indexOf('0 of 0') === 0)) {
+      $issueableHeader.append(`<span id="task_status">${newStateData.task_status}</span>`);
+    } else {
+      $issueableHeader.append('<span id="task_status"></span>');
+    }
+  } else {
+    tasksStates.newState = newStateData.task_status.indexOf('0 of 0') === 0;
+    tasksStates.currentState = tasks.indexOf('0 of 0') === 0;
+  }
+
+  if ($tasks.length !== 0 && !tasksStates.newState) {
+    $tasks.text(newStateData.task_status);
+    $tasksShort.text(newStateData.task_status);
+  } else if (tasksStates.currentState) {
+    $issueableHeader.append(`<span id="task_status">${newStateData.task_status}</span>`);
+  } else if (tasksStates.newState) {
+    $tasks.remove();
+    $tasksShort.remove();
+  }
+};
diff --git a/app/assets/javascripts/issue_show/index.js b/app/assets/javascripts/issue_show/index.js
index 4d491e70d83..eb20a597bb5 100644
--- a/app/assets/javascripts/issue_show/index.js
+++ b/app/assets/javascripts/issue_show/index.js
@@ -1,16 +1,16 @@
 import Vue from 'vue';
-import IssueTitle from './issue_title.vue';
+import IssueTitle from './issue_title_description.vue';
 import '../vue_shared/vue_resource_interceptor';
 
 (() => {
   const issueTitleData = document.querySelector('.issue-title-data').dataset;
-  const { initialTitle, endpoint } = issueTitleData;
+  const { canUpdateTasksClass, endpoint } = issueTitleData;
 
   const vm = new Vue({
     el: '.issue-title-entrypoint',
     render: createElement => createElement(IssueTitle, {
       props: {
-        initialTitle,
+        canUpdateTasksClass,
         endpoint,
       },
     }),
diff --git a/app/assets/javascripts/issue_show/issue_title.vue b/app/assets/javascripts/issue_show/issue_title.vue
deleted file mode 100644
index 00b0e56030a..00000000000
--- a/app/assets/javascripts/issue_show/issue_title.vue
+++ /dev/null
@@ -1,80 +0,0 @@
-<script>
-import Visibility from 'visibilityjs';
-import Poll from './../lib/utils/poll';
-import Service from './services/index';
-
-export default {
-  props: {
-    initialTitle: { required: true, type: String },
-    endpoint: { required: true, type: String },
-  },
-  data() {
-    const resource = new Service(this.$http, this.endpoint);
-
-    const poll = new Poll({
-      resource,
-      method: 'getTitle',
-      successCallback: (res) => {
-        this.renderResponse(res);
-      },
-      errorCallback: (err) => {
-        if (process.env.NODE_ENV !== 'production') {
-          // eslint-disable-next-line no-console
-          console.error('ISSUE SHOW TITLE REALTIME ERROR', err);
-        } else {
-          throw new Error(err);
-        }
-      },
-    });
-
-    return {
-      poll,
-      timeoutId: null,
-      title: this.initialTitle,
-    };
-  },
-  methods: {
-    renderResponse(res) {
-      const body = JSON.parse(res.body);
-      this.triggerAnimation(body);
-    },
-    triggerAnimation(body) {
-      const { title } = body;
-
-      /**
-      * since opacity is changed, even if there is no diff for Vue to update
-      * we must check the title even on a 304 to ensure no visual change
-      */
-      if (this.title === title) return;
-
-      this.$el.style.opacity = 0;
-
-      this.timeoutId = setTimeout(() => {
-        this.title = title;
-
-        this.$el.style.transition = 'opacity 0.2s ease';
-        this.$el.style.opacity = 1;
-
-        clearTimeout(this.timeoutId);
-      }, 100);
-    },
-  },
-  created() {
-    if (!Visibility.hidden()) {
-      this.poll.makeRequest();
-    }
-
-    Visibility.change(() => {
-      if (!Visibility.hidden()) {
-        this.poll.restart();
-      } else {
-        this.poll.stop();
-      }
-    });
-  },
-};
-</script>
-
-<template>
-  <h2 class="title" v-html="title"></h2>
-</template>
diff --git a/app/assets/javascripts/issue_show/issue_title_description.vue b/app/assets/javascripts/issue_show/issue_title_description.vue
new file mode 100644
index 00000000000..dc3ba2550c5
--- /dev/null
+++ b/app/assets/javascripts/issue_show/issue_title_description.vue
@@ -0,0 +1,180 @@
+<script>
+import Visibility from 'visibilityjs';
+import Poll from './../lib/utils/poll';
+import Service from './services/index';
+import tasks from './actions/tasks';
+
+export default {
+  props: {
+    endpoint: {
+      required: true,
+      type: String,
+    },
+    canUpdateTasksClass: {
+      required: true,
+      type: String,
+    },
+  },
+  data() {
+    const resource = new Service(this.$http, this.endpoint);
+
+    const poll = new Poll({
+      resource,
+      method: 'getTitle',
+      successCallback: (res) => {
+        this.renderResponse(res);
+      },
+      errorCallback: (err) => {
+        throw new Error(err);
+      },
+    });
+
+    return {
+      poll,
+      apiData: {},
+      tasks: '0 of 0',
+      title: null,
+      titleText: '',
+      titleFlag: {
+        pre: true,
+        pulse: false,
+      },
+      description: null,
+      descriptionText: '',
+      descriptionChange: false,
+      descriptionFlag: {
+        pre: true,
+        pulse: false,
+      },
+      timeAgoEl: $('.issue_edited_ago'),
+      titleEl: document.querySelector('title'),
+    };
+  },
+  methods: {
+    updateFlag(key, toggle) {
+      this[key].pre = toggle;
+      this[key].pulse = !toggle;
+    },
+    renderResponse(res) {
+      this.apiData = res.json();
+      this.triggerAnimation();
+    },
+    updateTaskHTML() {
+      tasks(this.apiData, this.tasks);
+    },
+    elementsToVisualize(noTitleChange, noDescriptionChange) {
+      if (!noTitleChange) {
+        this.titleText = this.apiData.title_text;
+        this.updateFlag('titleFlag', true);
+      }
+
+      if (!noDescriptionChange) {
+        // only change to true when we need to bind TaskLists the html of description
+        this.descriptionChange = true;
+        this.updateTaskHTML();
+        this.tasks = this.apiData.task_status;
+        this.updateFlag('descriptionFlag', true);
+      }
+    },
+    setTabTitle() {
+      const currentTabTitleScope = this.titleEl.innerText.split('·');
+      currentTabTitleScope[0] = `${this.titleText} (#${this.apiData.issue_number}) `;
+      this.titleEl.innerText = currentTabTitleScope.join('·');
+    },
+    animate(title, description) {
+      this.title = title;
+      this.description = description;
+      this.setTabTitle();
+
+      this.$nextTick(() => {
+        this.updateFlag('titleFlag', false);
+        this.updateFlag('descriptionFlag', false);
+      });
+    },
+    triggerAnimation() {
+      // always reset to false before checking the change
+      this.descriptionChange = false;
+
+      const { title, description } = this.apiData;
+      this.descriptionText = this.apiData.description_text;
+
+      const noTitleChange = this.title === title;
+      const noDescriptionChange = this.description === description;
+
+      /**
+      * since opacity is changed, even if there is no diff for Vue to update
+      * we must check the title/description even on a 304 to ensure no visual change
+      */
+      if (noTitleChange && noDescriptionChange) return;
+
+      this.elementsToVisualize(noTitleChange, noDescriptionChange);
+      this.animate(title, description);
+    },
+    updateEditedTimeAgo() {
+      const toolTipTime = gl.utils.formatDate(this.apiData.updated_at);
+      this.timeAgoEl.attr('datetime', this.apiData.updated_at);
+      this.timeAgoEl.attr('title', toolTipTime).tooltip('fixTitle');
+    },
+  },
+  created() {
+    if (!Visibility.hidden()) {
+      this.poll.makeRequest();
+    }
+
+    Visibility.change(() => {
+      if (!Visibility.hidden()) {
+        this.poll.restart();
+      } else {
+        this.poll.stop();
+      }
+    });
+  },
+  updated() {
+    // if new html is injected (description changed) - bind TaskList and call renderGFM
+    if (this.descriptionChange) {
+      this.updateEditedTimeAgo();
+
+      $(this.$refs['issue-content-container-gfm-entry']).renderGFM();
+
+      const tl = new gl.TaskList({
+        dataType: 'issue',
+        fieldName: 'description',
+        selector: '.detail-page-description',
+      });
+
+      return tl && null;
+    }
+
+    return null;
+  },
+};
+</script>
+
+<template>
+  <div>
+    <h2
+      class="title"
+      :class="{ 'issue-realtime-pre-pulse': titleFlag.pre, 'issue-realtime-trigger-pulse': titleFlag.pulse }"
+      ref="issue-title"
+      v-html="title"
+    >
+    </h2>
+    <div
+      class="description is-task-list-enabled"
+      :class="canUpdateTasksClass"
+      v-if="description"
+    >
+      <div
+        class="wiki"
+        :class="{ 'issue-realtime-pre-pulse': descriptionFlag.pre, 'issue-realtime-trigger-pulse': descriptionFlag.pulse }"
+        v-html="description"
+        ref="issue-content-container-gfm-entry"
+      >
+      </div>
+      <textarea
+        class="hidden js-task-list-field"
+        v-if="descriptionText"
+      >{{descriptionText}}</textarea>
+    </div>
+  </div>
+</template>
diff --git a/app/assets/javascripts/issue_status_select.js b/app/assets/javascripts/issue_status_select.js
index b2cfd3ef2a3..56cb536dcde 100644
--- a/app/assets/javascripts/issue_status_select.js
+++ b/app/assets/javascripts/issue_status_select.js
@@ -19,8 +19,8 @@
               return label;
             };
           })(this),
-          clicked: function(item, $el, e) {
-            return e.preventDefault();
+          clicked: function(options) {
+            return options.e.preventDefault();
           },
           id: function(obj, el) {
             return $(el).data("id");
diff --git a/app/assets/javascripts/issues_bulk_assignment.js b/app/assets/javascripts/issues_bulk_assignment.js
index e0ebd36a65c..fee3429e2b8 100644
--- a/app/assets/javascripts/issues_bulk_assignment.js
+++ b/app/assets/javascripts/issues_bulk_assignment.js
@@ -88,7 +88,10 @@
       const formData = {
         update: {
           state_event: this.form.find('input[name="update[state_event]"]').val(),
+          // For Merge Requests
           assignee_id: this.form.find('input[name="update[assignee_id]"]').val(),
+          // For Issues
+          assignee_ids: [this.form.find('input[name="update[assignee_ids][]"]').val()],
           milestone_id: this.form.find('input[name="update[milestone_id]"]').val(),
           issuable_ids: this.form.find('input[name="update[issuable_ids]"]').val(),
           subscription_event: this.form.find('input[name="update[subscription_event]"]').val(),
diff --git a/app/assets/javascripts/labels_select.js b/app/assets/javascripts/labels_select.js
index 9a60f5464df..ac5ce84e31b 100644
--- a/app/assets/javascripts/labels_select.js
+++ b/app/assets/javascripts/labels_select.js
@@ -330,7 +330,10 @@
           },
           multiSelect: $dropdown.hasClass('js-multiselect'),
           vue: $dropdown.hasClass('js-issue-board-sidebar'),
-          clicked: function(label, $el, e, isMarking) {
+          clicked: function(options) {
+            const { $el, e, isMarking } = options;
+            const label = options.selectedObj;
+
             var isIssueIndex, isMRIndex, page, boardsModel;
             var fadeOutLoader = () => {
               $loading.fadeOut();
@@ -352,7 +355,7 @@
 
             if ($dropdown.hasClass('js-filter-bulk-update')) {
               _this.enableBulkLabelDropdown();
-              _this.setDropdownData($dropdown, isMarking, this.id(label));
+              _this.setDropdownData($dropdown, isMarking, label.id);
               return;
             }
 
diff --git a/app/assets/javascripts/lib/utils/accessor.js b/app/assets/javascripts/lib/utils/accessor.js
new file mode 100644
index 00000000000..1d18992af63
--- /dev/null
+++ b/app/assets/javascripts/lib/utils/accessor.js
@@ -0,0 +1,47 @@
+function isPropertyAccessSafe(base, property) {
+  let safe;
+
+  try {
+    safe = !!base[property];
+  } catch (error) {
+    safe = false;
+  }
+
+  return safe;
+}
+
+function isFunctionCallSafe(base, functionName, ...args) {
+  let safe = true;
+
+  try {
+    base[functionName](...args);
+  } catch (error) {
+    safe = false;
+  }
+
+  return safe;
+}
+
+function isLocalStorageAccessSafe() {
+  let safe;
+
+  const TEST_KEY = 'isLocalStorageAccessSafe';
+  const TEST_VALUE = 'true';
+
+  safe = isPropertyAccessSafe(window, 'localStorage');
+  if (!safe) return safe;
+
+  safe = isFunctionCallSafe(window.localStorage, 'setItem', TEST_KEY, TEST_VALUE);
+
+  if (safe) window.localStorage.removeItem(TEST_KEY);
+
+  return safe;
+}
+
+const AccessorUtilities = {
+  isPropertyAccessSafe,
+  isFunctionCallSafe,
+  isLocalStorageAccessSafe,
+};
+
+export default AccessorUtilities;
diff --git a/app/assets/javascripts/lib/utils/ajax_cache.js b/app/assets/javascripts/lib/utils/ajax_cache.js
new file mode 100644
index 00000000000..d99eefb5089
--- /dev/null
+++ b/app/assets/javascripts/lib/utils/ajax_cache.js
@@ -0,0 +1,32 @@
+const AjaxCache = {
+  internalStorage: { },
+  get(endpoint) {
+    return this.internalStorage[endpoint];
+  },
+  hasData(endpoint) {
+    return Object.prototype.hasOwnProperty.call(this.internalStorage, endpoint);
+  },
+  purge(endpoint) {
+    delete this.internalStorage[endpoint];
+  },
+  retrieve(endpoint) {
+    if (AjaxCache.hasData(endpoint)) {
+      return Promise.resolve(AjaxCache.get(endpoint));
+    }
+
+    return new Promise((resolve, reject) => {
+      $.ajax(endpoint) // eslint-disable-line promise/catch-or-return
+      .then(data => resolve(data),
+        (jqXHR, textStatus, errorThrown) => {
+          const error = new Error(`${endpoint}: ${errorThrown}`);
+          error.textStatus = textStatus;
+          reject(error);
+        },
+      );
+    })
+    .then((data) => { this.internalStorage[endpoint] = data; })
+    .then(() => AjaxCache.get(endpoint));
+  },
+};
+
+export default AjaxCache;
diff --git a/app/assets/javascripts/main.js b/app/assets/javascripts/main.js
index 1c60b3b0b3b..c660d6919f6 100644
--- a/app/assets/javascripts/main.js
+++ b/app/assets/javascripts/main.js
@@ -157,7 +157,6 @@ import './single_file_diff';
 import './smart_interval';
 import './snippets_list';
 import './star';
-import './subbable_resource';
 import './subscription';
 import './subscription_select';
 import './syntax_highlight';
diff --git a/app/assets/javascripts/members.js b/app/assets/javascripts/members.js
index e3f367a11eb..8291b8c4a70 100644
--- a/app/assets/javascripts/members.js
+++ b/app/assets/javascripts/members.js
@@ -31,8 +31,8 @@
           toggleLabel(selected, $el) {
             return $el.text();
           },
-          clicked: (selected, $link) => {
-            this.formSubmit(null, $link);
+          clicked: (options) => {
+            this.formSubmit(null, options.$el);
           },
         });
       });
diff --git a/app/assets/javascripts/milestone_select.js b/app/assets/javascripts/milestone_select.js
index bebd0aa357e..11e68c0a3be 100644
--- a/app/assets/javascripts/milestone_select.js
+++ b/app/assets/javascripts/milestone_select.js
@@ -121,7 +121,10 @@
             return $value.css('display', '');
           },
           vue: $dropdown.hasClass('js-issue-board-sidebar'),
-          clicked: function(selected, $el, e) {
+          clicked: function(options) {
+            const { $el, e } = options;
+            let selected = options.selectedObj;
+
             var data, isIssueIndex, isMRIndex, page, boardsStore;
             page = $('body').data('page');
             isIssueIndex = page === 'projects:issues:index';
diff --git a/app/assets/javascripts/namespace_select.js b/app/assets/javascripts/namespace_select.js
index b98e6121967..36bc1257cef 100644
--- a/app/assets/javascripts/namespace_select.js
+++ b/app/assets/javascripts/namespace_select.js
@@ -58,7 +58,8 @@
       });
     }
 
-    NamespaceSelect.prototype.onSelectItem = function(item, el, e) {
+    NamespaceSelect.prototype.onSelectItem = function(options) {
+      const { e } = options;
       return e.preventDefault();
     };
 
diff --git a/app/assets/javascripts/notes.js b/app/assets/javascripts/notes.js
index 72709f68070..55391ebc089 100644
--- a/app/assets/javascripts/notes.js
+++ b/app/assets/javascripts/notes.js
@@ -1356,7 +1356,7 @@ const normalizeNewlines = function(str) {
 
       // Show updated comment content temporarily
       $noteBodyText.html(formContent);
-      $editingNote.removeClass('is-editing').addClass('being-posted fade-in-half');
+      $editingNote.removeClass('is-editing fade-in-full').addClass('being-posted fade-in-half');
       $editingNote.find('.note-headline-meta a').html('<i class="fa fa-spinner fa-spin" aria-label="Comment is being updated" aria-hidden="true"></i>');
 
       /* eslint-disable promise/catch-or-return */
diff --git a/app/assets/javascripts/project.js b/app/assets/javascripts/project.js
index f944fcc5a58..738e710deb9 100644
--- a/app/assets/javascripts/project.js
+++ b/app/assets/javascripts/project.js
@@ -112,7 +112,8 @@ import Cookies from 'js-cookie';
           toggleLabel: function(obj, $el) {
             return $el.text().trim();
           },
-          clicked: function(selected, $el, e) {
+          clicked: function(options) {
+            const { e } = options;
             e.preventDefault();
             if ($('input[name="ref"]').length) {
               var $form = $dropdown.closest('form');
diff --git a/app/assets/javascripts/protected_branches/protected_branch_access_dropdown.js b/app/assets/javascripts/protected_branches/protected_branch_access_dropdown.js
index e7fff57ff45..42993a252c3 100644
--- a/app/assets/javascripts/protected_branches/protected_branch_access_dropdown.js
+++ b/app/assets/javascripts/protected_branches/protected_branch_access_dropdown.js
@@ -19,7 +19,9 @@
             return 'Select';
           }
         },
-        clicked(item, $el, e) {
+        clicked(opts) {
+          const { e } = opts;
+
           e.preventDefault();
           onSelect();
         }
diff --git a/app/assets/javascripts/protected_branches/protected_branch_dropdown.js b/app/assets/javascripts/protected_branches/protected_branch_dropdown.js
index 1d4bb8a13d6..bc6110fcd4e 100644
--- a/app/assets/javascripts/protected_branches/protected_branch_dropdown.js
+++ b/app/assets/javascripts/protected_branches/protected_branch_dropdown.js
@@ -35,7 +35,8 @@ class ProtectedBranchDropdown {
         return _.escape(protectedBranch.id);
       },
       onFilter: this.toggleCreateNewButton.bind(this),
-      clicked: (item, $el, e) => {
+      clicked: (options) => {
+        const { $el, e } = options;
         e.preventDefault();
         this.onSelect();
       }
diff --git a/app/assets/javascripts/protected_tags/protected_tag_access_dropdown.js b/app/assets/javascripts/protected_tags/protected_tag_access_dropdown.js
index fff83f3af3b..d4c9a91a74a 100644
--- a/app/assets/javascripts/protected_tags/protected_tag_access_dropdown.js
+++ b/app/assets/javascripts/protected_tags/protected_tag_access_dropdown.js
@@ -17,8 +17,8 @@ export default class ProtectedTagAccessDropdown {
         }
         return 'Select';
       },
-      clicked(item, $el, e) {
-        e.preventDefault();
+      clicked(options) {
+        options.e.preventDefault();
         onSelect();
       },
     });
diff --git a/app/assets/javascripts/protected_tags/protected_tag_dropdown.js b/app/assets/javascripts/protected_tags/protected_tag_dropdown.js
index 5ff4e443262..068e9698e1d 100644
--- a/app/assets/javascripts/protected_tags/protected_tag_dropdown.js
+++ b/app/assets/javascripts/protected_tags/protected_tag_dropdown.js
@@ -39,8 +39,8 @@ export default class ProtectedTagDropdown {
         return _.escape(protectedTag.id);
       },
       onFilter: this.toggleCreateNewButton.bind(this),
-      clicked: (item, $el, e) => {
-        e.preventDefault();
+      clicked: (options) => {
+        options.e.preventDefault();
         this.onSelect();
       },
     });
diff --git a/app/assets/javascripts/raven/index.js b/app/assets/javascripts/raven/index.js
new file mode 100644
index 00000000000..5325e495815
--- /dev/null
+++ b/app/assets/javascripts/raven/index.js
@@ -0,0 +1,16 @@
+import RavenConfig from './raven_config';
+
+const index = function index() {
+  RavenConfig.init({
+    sentryDsn: gon.sentry_dsn,
+    currentUserId: gon.current_user_id,
+    whitelistUrls: [gon.gitlab_url],
+    isProduction: process.env.NODE_ENV,
+  });
+
+  return RavenConfig;
+};
+
+index();
+
+export default index;
diff --git a/app/assets/javascripts/raven/raven_config.js b/app/assets/javascripts/raven/raven_config.js
new file mode 100644
index 00000000000..c7fe1cacf49
--- /dev/null
+++ b/app/assets/javascripts/raven/raven_config.js
@@ -0,0 +1,100 @@
+import Raven from 'raven-js';
+
+const IGNORE_ERRORS = [
+  // Random plugins/extensions
+  'top.GLOBALS',
+  // See: http://blog.errorception.com/2012/03/tale-of-unfindable-js-error. html
+  'originalCreateNotification',
+  'canvas.contentDocument',
+  'MyApp_RemoveAllHighlights',
+  'http://tt.epicplay.com',
+  'Can\'t find variable: ZiteReader',
+  'jigsaw is not defined',
+  'ComboSearch is not defined',
+  'http://loading.retry.widdit.com/',
+  'atomicFindClose',
+  // Facebook borked
+  'fb_xd_fragment',
+  // ISP "optimizing" proxy - `Cache-Control: no-transform` seems to
+  // reduce this. (thanks @acdha)
+  // See http://stackoverflow.com/questions/4113268
+  'bmi_SafeAddOnload',
+  'EBCallBackMessageReceived',
+  // See http://toolbar.conduit.com/Developer/HtmlAndGadget/Methods/JSInjection.aspx
+  'conduitPage',
+];
+
+const IGNORE_URLS = [
+  // Facebook flakiness
+  /graph\.facebook\.com/i,
+  // Facebook blocked
+  /connect\.facebook\.net\/en_US\/all\.js/i,
+  // Woopra flakiness
+  /eatdifferent\.com\.woopra-ns\.com/i,
+  /static\.woopra\.com\/js\/woopra\.js/i,
+  // Chrome extensions
+  /extensions\//i,
+  /^chrome:\/\//i,
+  // Other plugins
+  /127\.0\.0\.1:4001\/isrunning/i,  // Cacaoweb
+  /webappstoolbarba\.texthelp\.com\//i,
+  /metrics\.itunes\.apple\.com\.edgesuite\.net\//i,
+];
+
+const SAMPLE_RATE = 95;
+
+const RavenConfig = {
+  IGNORE_ERRORS,
+  IGNORE_URLS,
+  SAMPLE_RATE,
+  init(options = {}) {
+    this.options = options;
+
+    this.configure();
+    this.bindRavenErrors();
+    if (this.options.currentUserId) this.setUser();
+  },
+
+  configure() {
+    Raven.config(this.options.sentryDsn, {
+      whitelistUrls: this.options.whitelistUrls,
+      environment: this.options.isProduction ? 'production' : 'development',
+      ignoreErrors: this.IGNORE_ERRORS,
+      ignoreUrls: this.IGNORE_URLS,
+      shouldSendCallback: this.shouldSendSample.bind(this),
+    }).install();
+  },
+
+  setUser() {
+    Raven.setUserContext({
+      id: this.options.currentUserId,
+    });
+  },
+
+  bindRavenErrors() {
+    window.$(document).on('ajaxError.raven', this.handleRavenErrors);
+  },
+
+  handleRavenErrors(event, req, config, err) {
+    const error = err || req.statusText;
+    const responseText = req.responseText || 'Unknown response text';
+
+    Raven.captureMessage(error, {
+      extra: {
+        type: config.type,
+        url: config.url,
+        data: config.data,
+        status: req.status,
+        response: responseText,
+        error,
+        event,
+      },
+    });
+  },
+
+  shouldSendSample() {
+    return Math.random() * 100 <= this.SAMPLE_RATE;
+  },
+};
+
+export default RavenConfig;
diff --git a/app/assets/javascripts/sidebar/components/assignees/assignee_title.js b/app/assets/javascripts/sidebar/components/assignees/assignee_title.js
new file mode 100644
index 00000000000..a9ad3708514
--- /dev/null
+++ b/app/assets/javascripts/sidebar/components/assignees/assignee_title.js
@@ -0,0 +1,41 @@
+export default {
+  name: 'AssigneeTitle',
+  props: {
+    loading: {
+      type: Boolean,
+      required: false,
+      default: false,
+    },
+    numberOfAssignees: {
+      type: Number,
+      required: true,
+    },
+    editable: {
+      type: Boolean,
+      required: true,
+    },
+  },
+  computed: {
+    assigneeTitle() {
+      const assignees = this.numberOfAssignees;
+      return assignees > 1 ? `${assignees} Assignees` : 'Assignee';
+    },
+  },
+  template: `
+    <div class="title hide-collapsed">
+      {{assigneeTitle}}
+      <i
+        v-if="loading"
+        aria-hidden="true"
+        class="fa fa-spinner fa-spin block-loading"
+      />
+      <a
+        v-if="editable"
+        class="edit-link pull-right"
+        href="#"
+      >
+        Edit
+      </a>
+    </div>
+  `,
+};
diff --git a/app/assets/javascripts/sidebar/components/assignees/assignees.js b/app/assets/javascripts/sidebar/components/assignees/assignees.js
new file mode 100644
index 00000000000..7e5feac622c
--- /dev/null
+++ b/app/assets/javascripts/sidebar/components/assignees/assignees.js
@@ -0,0 +1,224 @@
+export default {
+  name: 'Assignees',
+  data() {
+    return {
+      defaultRenderCount: 5,
+      defaultMaxCounter: 99,
+      showLess: true,
+    };
+  },
+  props: {
+    rootPath: {
+      type: String,
+      required: true,
+    },
+    users: {
+      type: Array,
+      required: true,
+    },
+    editable: {
+      type: Boolean,
+      required: true,
+    },
+  },
+  computed: {
+    firstUser() {
+      return this.users[0];
+    },
+    hasMoreThanTwoAssignees() {
+      return this.users.length > 2;
+    },
+    hasMoreThanOneAssignee() {
+      return this.users.length > 1;
+    },
+    hasAssignees() {
+      return this.users.length > 0;
+    },
+    hasNoUsers() {
+      return !this.users.length;
+    },
+    hasOneUser() {
+      return this.users.length === 1;
+    },
+    renderShowMoreSection() {
+      return this.users.length > this.defaultRenderCount;
+    },
+    numberOfHiddenAssignees() {
+      return this.users.length - this.defaultRenderCount;
+    },
+    isHiddenAssignees() {
+      return this.numberOfHiddenAssignees > 0;
+    },
+    hiddenAssigneesLabel() {
+      return `+ ${this.numberOfHiddenAssignees} more`;
+    },
+    collapsedTooltipTitle() {
+      const maxRender = Math.min(this.defaultRenderCount, this.users.length);
+      const renderUsers = this.users.slice(0, maxRender);
+      const names = renderUsers.map(u => u.name);
+
+      if (this.users.length > maxRender) {
+        names.push(`+ ${this.users.length - maxRender} more`);
+      }
+
+      return names.join(', ');
+    },
+    sidebarAvatarCounter() {
+      let counter = `+${this.users.length - 1}`;
+
+      if (this.users.length > this.defaultMaxCounter) {
+        counter = `${this.defaultMaxCounter}+`;
+      }
+
+      return counter;
+    },
+  },
+  methods: {
+    assignSelf() {
+      this.$emit('assign-self');
+    },
+    toggleShowLess() {
+      this.showLess = !this.showLess;
+    },
+    renderAssignee(index) {
+      return !this.showLess || (index < this.defaultRenderCount && this.showLess);
+    },
+    avatarUrl(user) {
+      return user.avatar || user.avatar_url;
+    },
+    assigneeUrl(user) {
+      return `${this.rootPath}${user.username}`;
+    },
+    assigneeAlt(user) {
+      return `${user.name}'s avatar`;
+    },
+    assigneeUsername(user) {
+      return `@${user.username}`;
+    },
+    shouldRenderCollapsedAssignee(index) {
+      const firstTwo = this.users.length <= 2 && index <= 2;
+
+      return index === 0 || firstTwo;
+    },
+  },
+  template: `
+    <div>
+      <div
+        class="sidebar-collapsed-icon sidebar-collapsed-user"
+        :class="{ 'multiple-users': hasMoreThanOneAssignee, 'has-tooltip': hasAssignees }"
+        data-container="body"
+        data-placement="left"
+        :title="collapsedTooltipTitle"
+      >
+        <i
+          v-if="hasNoUsers"
+          aria-label="No Assignee"
+          class="fa fa-user"
+        />
+        <button
+          type="button"
+          class="btn-link"
+          v-for="(user, index) in users"
+          v-if="shouldRenderCollapsedAssignee(index)"
+        >
+          <img
+            width="24"
+            class="avatar avatar-inline s24"
+            :alt="assigneeAlt(user)"
+            :src="avatarUrl(user)"
+          />
+          <span class="author">
+            {{ user.name }}
+          </span>
+        </button>
+        <button
+          v-if="hasMoreThanTwoAssignees"
+          class="btn-link"
+          type="button"
+        >
+          <span
+            class="avatar-counter sidebar-avatar-counter"
+          >
+            {{ sidebarAvatarCounter }}
+          </span>
+        </button>
+      </div>
+      <div class="value hide-collapsed">
+        <template v-if="hasNoUsers">
+          <span class="assign-yourself no-value">
+            No assignee
+            <template v-if="editable">
+             -
+              <button
+                type="button"
+                class="btn-link"
+                @click="assignSelf"
+              >
+                assign yourself
+              </button>
+            </template>
+          </span>
+        </template>
+        <template v-else-if="hasOneUser">
+          <a
+            class="author_link bold"
+            :href="assigneeUrl(firstUser)"
+          >
+            <img
+              width="32"
+              class="avatar avatar-inline s32"
+              :alt="assigneeAlt(firstUser)"
+              :src="avatarUrl(firstUser)"
+            />
+            <span class="author">
+              {{ firstUser.name }}
+            </span>
+            <span class="username">
+              {{ assigneeUsername(firstUser) }}
+            </span>
+          </a>
+        </template>
+        <template v-else>
+          <div class="user-list">
+            <div
+              class="user-item"
+              v-for="(user, index) in users"
+              v-if="renderAssignee(index)"
+            >
+              <a
+                class="user-link has-tooltip"
+                data-placement="bottom"
+                :href="assigneeUrl(user)"
+                :data-title="user.name"
+              >
+                <img
+                  width="32"
+                  class="avatar avatar-inline s32"
+                  :alt="assigneeAlt(user)"
+                  :src="avatarUrl(user)"
+                />
+              </a>
+            </div>
+          </div>
+          <div
+            v-if="renderShowMoreSection"
+            class="user-list-more"
+          >
+            <button
+              type="button"
+              class="btn-link"
+              @click="toggleShowLess"
+            >
+              <template v-if="showLess">
+                {{ hiddenAssigneesLabel }}
+              </template>
+              <template v-else>
+                - show less
+              </template>
+            </button>
+          </div>
+        </template>
+      </div>
+    </div>
+  `,
+};
diff --git a/app/assets/javascripts/sidebar/components/assignees/sidebar_assignees.js b/app/assets/javascripts/sidebar/components/assignees/sidebar_assignees.js
new file mode 100644
index 00000000000..1488a66c695
--- /dev/null
+++ b/app/assets/javascripts/sidebar/components/assignees/sidebar_assignees.js
@@ -0,0 +1,84 @@
+/* global Flash */
+
+import AssigneeTitle from './assignee_title';
+import Assignees from './assignees';
+
+import Store from '../../stores/sidebar_store';
+import Mediator from '../../sidebar_mediator';
+
+import eventHub from '../../event_hub';
+
+export default {
+  name: 'SidebarAssignees',
+  data() {
+    return {
+      mediator: new Mediator(),
+      store: new Store(),
+      loading: false,
+      field: '',
+    };
+  },
+  components: {
+    'assignee-title': AssigneeTitle,
+    assignees: Assignees,
+  },
+  methods: {
+    assignSelf() {
+      // Notify gl dropdown that we are now assigning to current user
+      this.$el.parentElement.dispatchEvent(new Event('assignYourself'));
+
+      this.mediator.assignYourself();
+      this.saveAssignees();
+    },
+    saveAssignees() {
+      this.loading = true;
+
+      function setLoadingFalse() {
+        this.loading = false;
+      }
+
+      this.mediator.saveAssignees(this.field)
+        .then(setLoadingFalse.bind(this))
+        .catch(() => {
+          setLoadingFalse();
+          return new Flash('Error occurred when saving assignees');
+        });
+    },
+  },
+  created() {
+    this.removeAssignee = this.store.removeAssignee.bind(this.store);
+    this.addAssignee = this.store.addAssignee.bind(this.store);
+    this.removeAllAssignees = this.store.removeAllAssignees.bind(this.store);
+
+    // Get events from glDropdown
+    eventHub.$on('sidebar.removeAssignee', this.removeAssignee);
+    eventHub.$on('sidebar.addAssignee', this.addAssignee);
+    eventHub.$on('sidebar.removeAllAssignees', this.removeAllAssignees);
+    eventHub.$on('sidebar.saveAssignees', this.saveAssignees);
+  },
+  beforeDestroy() {
+    eventHub.$off('sidebar.removeAssignee', this.removeAssignee);
+    eventHub.$off('sidebar.addAssignee', this.addAssignee);
+    eventHub.$off('sidebar.removeAllAssignees', this.removeAllAssignees);
+    eventHub.$off('sidebar.saveAssignees', this.saveAssignees);
+  },
+  beforeMount() {
+    this.field = this.$el.dataset.field;
+  },
+  template: `
+    <div>
+      <assignee-title
+        :number-of-assignees="store.assignees.length"
+        :loading="loading"
+        :editable="store.editable"
+      />
+      <assignees
+        class="value"
+        :root-path="store.rootPath"
+        :users="store.assignees"
+        :editable="store.editable"
+        @assign-self="assignSelf"
+      />
+    </div>
+  `,
+};
diff --git a/app/assets/javascripts/sidebar/components/time_tracking/collapsed_state.js b/app/assets/javascripts/sidebar/components/time_tracking/collapsed_state.js
new file mode 100644
index 00000000000..0da265053bd
--- /dev/null
+++ b/app/assets/javascripts/sidebar/components/time_tracking/collapsed_state.js
@@ -0,0 +1,97 @@
+import stopwatchSvg from 'icons/_icon_stopwatch.svg';
+
+import '../../../lib/utils/pretty_time';
+
+export default {
+  name: 'time-tracking-collapsed-state',
+  props: {
+    showComparisonState: {
+      type: Boolean,
+      required: true,
+    },
+    showSpentOnlyState: {
+      type: Boolean,
+      required: true,
+    },
+    showEstimateOnlyState: {
+      type: Boolean,
+      required: true,
+    },
+    showNoTimeTrackingState: {
+      type: Boolean,
+      required: true,
+    },
+    timeSpentHumanReadable: {
+      type: String,
+      required: false,
+      default: '',
+    },
+    timeEstimateHumanReadable: {
+      type: String,
+      required: false,
+      default: '',
+    },
+  },
+  computed: {
+    timeSpent() {
+      return this.abbreviateTime(this.timeSpentHumanReadable);
+    },
+    timeEstimate() {
+      return this.abbreviateTime(this.timeEstimateHumanReadable);
+    },
+    divClass() {
+      if (this.showComparisonState) {
+        return 'compare';
+      } else if (this.showEstimateOnlyState) {
+        return 'estimate-only';
+      } else if (this.showSpentOnlyState) {
+        return 'spend-only';
+      } else if (this.showNoTimeTrackingState) {
+        return 'no-tracking';
+      }
+
+      return '';
+    },
+    spanClass() {
+      if (this.showComparisonState) {
+        return '';
+      } else if (this.showEstimateOnlyState || this.showSpentOnlyState) {
+        return 'bold';
+      } else if (this.showNoTimeTrackingState) {
+        return 'no-value';
+      }
+
+      return '';
+    },
+    text() {
+      if (this.showComparisonState) {
+        return `${this.timeSpent} / ${this.timeEstimate}`;
+      } else if (this.showEstimateOnlyState) {
+        return `-- / ${this.timeEstimate}`;
+      } else if (this.showSpentOnlyState) {
+        return `${this.timeSpent} / --`;
+      } else if (this.showNoTimeTrackingState) {
+        return 'None';
+      }
+
+      return '';
+    },
+  },
+  methods: {
+    abbreviateTime(timeStr) {
+      return gl.utils.prettyTime.abbreviateTime(timeStr);
+    },
+  },
+  template: `
+    <div class="sidebar-collapsed-icon">
+      ${stopwatchSvg}
+      <div class="time-tracking-collapsed-summary">
+        <div :class="divClass">
+          <span :class="spanClass">
+            {{ text }}
+          </span>
+        </div>
+      </div>
+    </div>
+    `,
+};
diff --git a/app/assets/javascripts/sidebar/components/time_tracking/comparison_pane.js b/app/assets/javascripts/sidebar/components/time_tracking/comparison_pane.js
new file mode 100644
index 00000000000..40f5c89c5bb
--- /dev/null
+++ b/app/assets/javascripts/sidebar/components/time_tracking/comparison_pane.js
@@ -0,0 +1,98 @@
+import '../../../lib/utils/pretty_time';
+
+const prettyTime = gl.utils.prettyTime;
+
+export default {
+  name: 'time-tracking-comparison-pane',
+  props: {
+    timeSpent: {
+      type: Number,
+      required: true,
+    },
+    timeEstimate: {
+      type: Number,
+      required: true,
+    },
+    timeSpentHumanReadable: {
+      type: String,
+      required: true,
+    },
+    timeEstimateHumanReadable: {
+      type: String,
+      required: true,
+    },
+  },
+  computed: {
+    parsedRemaining() {
+      const diffSeconds = this.timeEstimate - this.timeSpent;
+      return prettyTime.parseSeconds(diffSeconds);
+    },
+    timeRemainingHumanReadable() {
+      return prettyTime.stringifyTime(this.parsedRemaining);
+    },
+    timeRemainingTooltip() {
+      const prefix = this.timeRemainingMinutes < 0 ? 'Over by' : 'Time remaining:';
+      return `${prefix} ${this.timeRemainingHumanReadable}`;
+    },
+    /* Diff values for comparison meter */
+    timeRemainingMinutes() {
+      return this.timeEstimate - this.timeSpent;
+    },
+    timeRemainingPercent() {
+      return `${Math.floor((this.timeSpent / this.timeEstimate) * 100)}%`;
+    },
+    timeRemainingStatusClass() {
+      return this.timeEstimate >= this.timeSpent ? 'within_estimate' : 'over_estimate';
+    },
+    /* Parsed time values */
+    parsedEstimate() {
+      return prettyTime.parseSeconds(this.timeEstimate);
+    },
+    parsedSpent() {
+      return prettyTime.parseSeconds(this.timeSpent);
+    },
+  },
+  template: `
+    <div class="time-tracking-comparison-pane">
+      <div
+        class="compare-meter"
+        data-toggle="tooltip"
+        data-placement="top"
+        role="timeRemainingDisplay"
+        :aria-valuenow="timeRemainingTooltip"
+        :title="timeRemainingTooltip"
+        :data-original-title="timeRemainingTooltip"
+        :class="timeRemainingStatusClass"
+      >
+        <div
+          class="meter-container"
+          role="timeSpentPercent"
+          :aria-valuenow="timeRemainingPercent"
+        >
+          <div
+            :style="{ width: timeRemainingPercent }"
+            class="meter-fill"
+          />
+        </div>
+        <div class="compare-display-container">
+          <div class="compare-display pull-left">
+            <span class="compare-label">
+              Spent
+            </span>
+            <span class="compare-value spent">
+              {{ timeSpentHumanReadable }}
+            </span>
+          </div>
+          <div class="compare-display estimated pull-right">
+            <span class="compare-label">
+              Est
+            </span>
+            <span class="compare-value">
+              {{ timeEstimateHumanReadable }}
+            </span>
+          </div>
+        </div>
+      </div>
+    </div>
+  `,
+};
diff --git a/app/assets/javascripts/sidebar/components/time_tracking/estimate_only_pane.js b/app/assets/javascripts/sidebar/components/time_tracking/estimate_only_pane.js
new file mode 100644
index 00000000000..ad1b9179db0
--- /dev/null
+++ b/app/assets/javascripts/sidebar/components/time_tracking/estimate_only_pane.js
@@ -0,0 +1,17 @@
+export default {
+  name: 'time-tracking-estimate-only-pane',
+  props: {
+    timeEstimateHumanReadable: {
+      type: String,
+      required: true,
+    },
+  },
+  template: `
+    <div class="time-tracking-estimate-only-pane">
+      <span class="bold">
+        Estimated:
+      </span>
+      {{ timeEstimateHumanReadable }}
+    </div>
+  `,
+};
diff --git a/app/assets/javascripts/sidebar/components/time_tracking/help_state.js b/app/assets/javascripts/sidebar/components/time_tracking/help_state.js
new file mode 100644
index 00000000000..b2a77462fe0
--- /dev/null
+++ b/app/assets/javascripts/sidebar/components/time_tracking/help_state.js
@@ -0,0 +1,44 @@
+export default {
+  name: 'time-tracking-help-state',
+  props: {
+    rootPath: {
+      type: String,
+      required: true,
+    },
+  },
+  computed: {
+    href() {
+      return `${this.rootPath}help/workflow/time_tracking.md`;
+    },
+  },
+  template: `
+    <div class="time-tracking-help-state">
+      <div class="time-tracking-info">
+        <h4>
+          Track time with slash commands
+        </h4>
+        <p>
+          Slash commands can be used in the issues description and comment boxes.
+        </p>
+        <p>
+          <code>
+            /estimate
+          </code>
+          will update the estimated time with the latest command.
+        </p>
+        <p>
+          <code>
+            /spend
+          </code>
+          will update the sum of the time spent.
+        </p>
+        <a
+          class="btn btn-default learn-more-button"
+          :href="href"
+        >
+          Learn more
+        </a>
+      </div>
+    </div>
+  `,
+};
diff --git a/app/assets/javascripts/sidebar/components/time_tracking/no_tracking_pane.js b/app/assets/javascripts/sidebar/components/time_tracking/no_tracking_pane.js
new file mode 100644
index 00000000000..d1dd1dcdd27
--- /dev/null
+++ b/app/assets/javascripts/sidebar/components/time_tracking/no_tracking_pane.js
@@ -0,0 +1,10 @@
+export default {
+  name: 'time-tracking-no-tracking-pane',
+  template: `
+    <div class="time-tracking-no-tracking-pane">
+      <span class="no-value">
+        No estimate or time spent
+      </span>
+    </div>
+  `,
+};
diff --git a/app/assets/javascripts/sidebar/components/time_tracking/sidebar_time_tracking.js b/app/assets/javascripts/sidebar/components/time_tracking/sidebar_time_tracking.js
new file mode 100644
index 00000000000..244b67b3ad9
--- /dev/null
+++ b/app/assets/javascripts/sidebar/components/time_tracking/sidebar_time_tracking.js
@@ -0,0 +1,51 @@
+import '~/smart_interval';
+
+import timeTracker from './time_tracker';
+
+import Store from '../../stores/sidebar_store';
+import Mediator from '../../sidebar_mediator';
+
+export default {
+  data() {
+    return {
+      mediator: new Mediator(),
+      store: new Store(),
+    };
+  },
+  components: {
+    'issuable-time-tracker': timeTracker,
+  },
+  methods: {
+    listenForSlashCommands() {
+      $(document).on('ajax:success', '.gfm-form', this.slashCommandListened);
+    },
+    slashCommandListened(e, data) {
+      const subscribedCommands = ['spend_time', 'time_estimate'];
+      let changedCommands;
+      if (data !== undefined) {
+        changedCommands = data.commands_changes
+          ? Object.keys(data.commands_changes)
+          : [];
+      } else {
+        changedCommands = [];
+      }
+      if (changedCommands && _.intersection(subscribedCommands, changedCommands).length) {
+        this.mediator.fetch();
+      }
+    },
+  },
+  mounted() {
+    this.listenForSlashCommands();
+  },
+  template: `
+    <div class="block">
+      <issuable-time-tracker
+        :time_estimate="store.timeEstimate"
+        :time_spent="store.totalTimeSpent"
+        :human_time_estimate="store.humanTimeEstimate"
+        :human_time_spent="store.humanTotalTimeSpent"
+        :rootPath="store.rootPath"
+      />
+    </div>
+  `,
+};
diff --git a/app/assets/javascripts/sidebar/components/time_tracking/spent_only_pane.js b/app/assets/javascripts/sidebar/components/time_tracking/spent_only_pane.js
new file mode 100644
index 00000000000..bf987562647
--- /dev/null
+++ b/app/assets/javascripts/sidebar/components/time_tracking/spent_only_pane.js
@@ -0,0 +1,15 @@
+export default {
+  name: 'time-tracking-spent-only-pane',
+  props: {
+    timeSpentHumanReadable: {
+      type: String,
+      required: true,
+    },
+  },
+  template: `
+    <div class="time-tracking-spend-only-pane">
+      <span class="bold">Spent:</span>
+      {{ timeSpentHumanReadable }}
+    </div>
+  `,
+};
diff --git a/app/assets/javascripts/sidebar/components/time_tracking/time_tracker.js b/app/assets/javascripts/sidebar/components/time_tracking/time_tracker.js
new file mode 100644
index 00000000000..ed0d71a4f79
--- /dev/null
+++ b/app/assets/javascripts/sidebar/components/time_tracking/time_tracker.js
@@ -0,0 +1,163 @@
+import timeTrackingHelpState from './help_state';
+import timeTrackingCollapsedState from './collapsed_state';
+import timeTrackingSpentOnlyPane from './spent_only_pane';
+import timeTrackingNoTrackingPane from './no_tracking_pane';
+import timeTrackingEstimateOnlyPane from './estimate_only_pane';
+import timeTrackingComparisonPane from './comparison_pane';
+
+import eventHub from '../../event_hub';
+
+export default {
+  name: 'issuable-time-tracker',
+  props: {
+    time_estimate: {
+      type: Number,
+      required: true,
+    },
+    time_spent: {
+      type: Number,
+      required: true,
+    },
+    human_time_estimate: {
+      type: String,
+      required: false,
+      default: '',
+    },
+    human_time_spent: {
+      type: String,
+      required: false,
+      default: '',
+    },
+    rootPath: {
+      type: String,
+      required: true,
+    },
+  },
+  data() {
+    return {
+      showHelp: false,
+    };
+  },
+  components: {
+    'time-tracking-collapsed-state': timeTrackingCollapsedState,
+    'time-tracking-estimate-only-pane': timeTrackingEstimateOnlyPane,
+    'time-tracking-spent-only-pane': timeTrackingSpentOnlyPane,
+    'time-tracking-no-tracking-pane': timeTrackingNoTrackingPane,
+    'time-tracking-comparison-pane': timeTrackingComparisonPane,
+    'time-tracking-help-state': timeTrackingHelpState,
+  },
+  computed: {
+    timeSpent() {
+      return this.time_spent;
+    },
+    timeEstimate() {
+      return this.time_estimate;
+    },
+    timeEstimateHumanReadable() {
+      return this.human_time_estimate;
+    },
+    timeSpentHumanReadable() {
+      return this.human_time_spent;
+    },
+    hasTimeSpent() {
+      return !!this.timeSpent;
+    },
+    hasTimeEstimate() {
+      return !!this.timeEstimate;
+    },
+    showComparisonState() {
+      return this.hasTimeEstimate && this.hasTimeSpent;
+    },
+    showEstimateOnlyState() {
+      return this.hasTimeEstimate && !this.hasTimeSpent;
+    },
+    showSpentOnlyState() {
+      return this.hasTimeSpent && !this.hasTimeEstimate;
+    },
+    showNoTimeTrackingState() {
+      return !this.hasTimeEstimate && !this.hasTimeSpent;
+    },
+    showHelpState() {
+      return !!this.showHelp;
+    },
+  },
+  methods: {
+    toggleHelpState(show) {
+      this.showHelp = show;
+    },
+    update(data) {
+      this.time_estimate = data.time_estimate;
+      this.time_spent = data.time_spent;
+      this.human_time_estimate = data.human_time_estimate;
+      this.human_time_spent = data.human_time_spent;
+    },
+  },
+  created() {
+    eventHub.$on('timeTracker:updateData', this.update);
+  },
+  template: `
+    <div
+      class="time_tracker time-tracking-component-wrap"
+      v-cloak
+    >
+      <time-tracking-collapsed-state
+        :show-comparison-state="showComparisonState"
+        :show-no-time-tracking-state="showNoTimeTrackingState"
+        :show-help-state="showHelpState"
+        :show-spent-only-state="showSpentOnlyState"
+        :show-estimate-only-state="showEstimateOnlyState"
+        :time-spent-human-readable="timeSpentHumanReadable"
+        :time-estimate-human-readable="timeEstimateHumanReadable"
+      />
+      <div class="title hide-collapsed">
+        Time tracking
+        <div
+          class="help-button pull-right"
+          v-if="!showHelpState"
+          @click="toggleHelpState(true)"
+        >
+            <i
+              class="fa fa-question-circle"
+              aria-hidden="true"
+            />
+        </div>
+        <div
+          class="close-help-button pull-right"
+          v-if="showHelpState"
+          @click="toggleHelpState(false)"
+        >
+          <i
+            class="fa fa-close"
+            aria-hidden="true"
+          />
+        </div>
+      </div>
+      <div class="time-tracking-content hide-collapsed">
+        <time-tracking-estimate-only-pane
+          v-if="showEstimateOnlyState"
+          :time-estimate-human-readable="timeEstimateHumanReadable"
+        />
+        <time-tracking-spent-only-pane
+          v-if="showSpentOnlyState"
+          :time-spent-human-readable="timeSpentHumanReadable"
+        />
+        <time-tracking-no-tracking-pane
+          v-if="showNoTimeTrackingState"
+        />
+        <time-tracking-comparison-pane
+          v-if="showComparisonState"
+          :time-estimate="timeEstimate"
+          :time-spent="timeSpent"
+          :time-spent-human-readable="timeSpentHumanReadable"
+          :time-estimate-human-readable="timeEstimateHumanReadable"
+        />
+        <transition name="help-state-toggle">
+          <time-tracking-help-state
+            v-if="showHelpState"
+            :rootPath="rootPath"
+          />
+        </transition>
+      </div>
+    </div>
+  `,
+};
diff --git a/app/assets/javascripts/sidebar/event_hub.js b/app/assets/javascripts/sidebar/event_hub.js
new file mode 100644
index 00000000000..0948c2e5352
--- /dev/null
+++ b/app/assets/javascripts/sidebar/event_hub.js
@@ -0,0 +1,3 @@
+import Vue from 'vue';
+
+export default new Vue();
diff --git a/app/assets/javascripts/sidebar/services/sidebar_service.js b/app/assets/javascripts/sidebar/services/sidebar_service.js
new file mode 100644
index 00000000000..5a82d01dc41
--- /dev/null
+++ b/app/assets/javascripts/sidebar/services/sidebar_service.js
@@ -0,0 +1,28 @@
+import Vue from 'vue';
+import VueResource from 'vue-resource';
+
+Vue.use(VueResource);
+
+export default class SidebarService {
+  constructor(endpoint) {
+    if (!SidebarService.singleton) {
+      this.endpoint = endpoint;
+
+      SidebarService.singleton = this;
+    }
+
+    return SidebarService.singleton;
+  }
+
+  get() {
+    return Vue.http.get(this.endpoint);
+  }
+
+  update(key, data) {
+    return Vue.http.put(this.endpoint, {
+      [key]: data,
+    }, {
+      emulateJSON: true,
+    });
+  }
+}
diff --git a/app/assets/javascripts/sidebar/sidebar_bundle.js b/app/assets/javascripts/sidebar/sidebar_bundle.js
new file mode 100644
index 00000000000..2b02af87d8a
--- /dev/null
+++ b/app/assets/javascripts/sidebar/sidebar_bundle.js
@@ -0,0 +1,24 @@
+import Vue from 'vue';
+import sidebarTimeTracking from './components/time_tracking/sidebar_time_tracking';
+import sidebarAssignees from './components/assignees/sidebar_assignees';
+
+import Mediator from './sidebar_mediator';
+
+function domContentLoaded() {
+  const mediator = new Mediator(gl.sidebarOptions);
+  mediator.fetch();
+
+  const sidebarAssigneesEl = document.querySelector('#js-vue-sidebar-assignees');
+
+  // Only create the sidebarAssignees vue app if it is found in the DOM
+  // We currently do not use sidebarAssignees for the MR page
+  if (sidebarAssigneesEl) {
+    new Vue(sidebarAssignees).$mount(sidebarAssigneesEl);
+  }
+
+  new Vue(sidebarTimeTracking).$mount('#issuable-time-tracker');
+}
+
+document.addEventListener('DOMContentLoaded', domContentLoaded);
+
+export default domContentLoaded;
diff --git a/app/assets/javascripts/sidebar/sidebar_mediator.js b/app/assets/javascripts/sidebar/sidebar_mediator.js
new file mode 100644
index 00000000000..5ccfb4ee9c1
--- /dev/null
+++ b/app/assets/javascripts/sidebar/sidebar_mediator.js
@@ -0,0 +1,38 @@
+/* global Flash */
+
+import Service from './services/sidebar_service';
+import Store from './stores/sidebar_store';
+
+export default class SidebarMediator {
+  constructor(options) {
+    if (!SidebarMediator.singleton) {
+      this.store = new Store(options);
+      this.service = new Service(options.endpoint);
+      SidebarMediator.singleton = this;
+    }
+
+    return SidebarMediator.singleton;
+  }
+
+  assignYourself() {
+    this.store.addAssignee(this.store.currentUser);
+  }
+
+  saveAssignees(field) {
+    const selected = this.store.assignees.map(u => u.id);
+
+    // If there are no ids, that means we have to unassign (which is id = 0)
+    // And it only accepts an array, hence [0]
+    return this.service.update(field, selected.length === 0 ? [0] : selected);
+  }
+
+  fetch() {
+    this.service.get()
+      .then((response) => {
+        const data = response.json();
+        this.store.setAssigneeData(data);
+        this.store.setTimeTrackingData(data);
+      })
+      .catch(() => new Flash('Error occured when fetching sidebar data'));
+  }
+}
diff --git a/app/assets/javascripts/sidebar/stores/sidebar_store.js b/app/assets/javascripts/sidebar/stores/sidebar_store.js
new file mode 100644
index 00000000000..2d44c05bb8d
--- /dev/null
+++ b/app/assets/javascripts/sidebar/stores/sidebar_store.js
@@ -0,0 +1,52 @@
+export default class SidebarStore {
+  constructor(store) {
+    if (!SidebarStore.singleton) {
+      const { currentUser, rootPath, editable } = store;
+      this.currentUser = currentUser;
+      this.rootPath = rootPath;
+      this.editable = editable;
+      this.timeEstimate = 0;
+      this.totalTimeSpent = 0;
+      this.humanTimeEstimate = '';
+      this.humanTimeSpent = '';
+      this.assignees = [];
+
+      SidebarStore.singleton = this;
+    }
+
+    return SidebarStore.singleton;
+  }
+
+  setAssigneeData(data) {
+    if (data.assignees) {
+      this.assignees = data.assignees;
+    }
+  }
+
+  setTimeTrackingData(data) {
+    this.timeEstimate = data.time_estimate;
+    this.totalTimeSpent = data.total_time_spent;
+    this.humanTimeEstimate = data.human_time_estimate;
+    this.humanTotalTimeSpent = data.human_total_time_spent;
+  }
+
+  addAssignee(assignee) {
+    if (!this.findAssignee(assignee)) {
+      this.assignees.push(assignee);
+    }
+  }
+
+  findAssignee(findAssignee) {
+    return this.assignees.filter(assignee => assignee.id === findAssignee.id)[0];
+  }
+
+  removeAssignee(removeAssignee) {
+    if (removeAssignee) {
+      this.assignees = this.assignees.filter(assignee => assignee.id !== removeAssignee.id);
+    }
+  }
+
+  removeAllAssignees() {
+    this.assignees = [];
+  }
+}
diff --git a/app/assets/javascripts/signin_tabs_memoizer.js b/app/assets/javascripts/signin_tabs_memoizer.js
index d811d1cd53a..2587facc582 100644
--- a/app/assets/javascripts/signin_tabs_memoizer.js
+++ b/app/assets/javascripts/signin_tabs_memoizer.js
@@ -1,5 +1,7 @@
 /* eslint no-param-reassign: ["error", { "props": false }]*/
 /* eslint no-new: "off" */
+import AccessorUtilities from './lib/utils/accessor';
+
 ((global) => {
   /**
    * Memorize the last selected tab after reloading a page.
@@ -9,6 +11,8 @@
     constructor({ currentTabKey = 'current_signin_tab', tabSelector = 'ul.nav-tabs' } = {}) {
       this.currentTabKey = currentTabKey;
       this.tabSelector = tabSelector;
+      this.isLocalStorageAvailable = AccessorUtilities.isLocalStorageAccessSafe();
+
       this.bootstrap();
     }
 
@@ -37,11 +41,15 @@
     }
 
     saveData(val) {
-      localStorage.setItem(this.currentTabKey, val);
+      if (!this.isLocalStorageAvailable) return undefined;
+
+      return window.localStorage.setItem(this.currentTabKey, val);
     }
 
     readData() {
-      return localStorage.getItem(this.currentTabKey);
+      if (!this.isLocalStorageAvailable) return null;
+
+      return window.localStorage.getItem(this.currentTabKey);
     }
   }
 
diff --git a/app/assets/javascripts/subbable_resource.js b/app/assets/javascripts/subbable_resource.js
deleted file mode 100644
index d8191605128..00000000000
--- a/app/assets/javascripts/subbable_resource.js
+++ /dev/null
@@ -1,51 +0,0 @@
-(() => {
-/*
-*   SubbableResource can be extended to provide a pubsub-style service for one-off REST
-*   calls. Subscribe by passing a callback or render method you will use to handle responses.
- *
-* */
-
-  class SubbableResource {
-    constructor(resourcePath) {
-      this.endpoint = resourcePath;
-
-      // TODO: Switch to axios.create
-      this.resource = $.ajax;
-      this.subscribers = [];
-    }
-
-    subscribe(callback) {
-      this.subscribers.push(callback);
-    }
-
-    publish(newResponse) {
-      const responseCopy = _.extend({}, newResponse);
-      this.subscribers.forEach((fn) => {
-        fn(responseCopy);
-      });
-      return newResponse;
-    }
-
-    get(payload) {
-      return this.resource(payload)
-        .then(data => this.publish(data));
-    }
-
-    post(payload) {
-      return this.resource(payload)
-        .then(data => this.publish(data));
-    }
-
-    put(payload) {
-      return this.resource(payload)
-        .then(data => this.publish(data));
-    }
-
-    delete(payload) {
-      return this.resource(payload)
-        .then(data => this.publish(data));
-    }
-  }
-
-  gl.SubbableResource = SubbableResource;
-})(window.gl || (window.gl = {}));
diff --git a/app/assets/javascripts/subscription_select.js b/app/assets/javascripts/subscription_select.js
index 8b25f43ffc7..0cd591c7320 100644
--- a/app/assets/javascripts/subscription_select.js
+++ b/app/assets/javascripts/subscription_select.js
@@ -19,8 +19,8 @@
               return label;
             };
           })(this),
-          clicked: function(item, $el, e) {
-            return e.preventDefault();
+          clicked: function(options) {
+            return options.e.preventDefault();
           },
           id: function(obj, el) {
             return $(el).data("id");
diff --git a/app/assets/javascripts/users/calendar.js b/app/assets/javascripts/users/calendar.js
index 754d448564f..32ffa2f0ac0 100644
--- a/app/assets/javascripts/users/calendar.js
+++ b/app/assets/javascripts/users/calendar.js
@@ -168,15 +168,23 @@ import d3 from 'd3';
     };
 
     Calendar.prototype.renderKey = function() {
-      var keyColors;
-      keyColors = ['#ededed', this.colorKey(0), this.colorKey(1), this.colorKey(2), this.colorKey(3)];
-      return this.svg.append('g').attr('transform', "translate(18, " + (this.daySizeWithSpace * 8 + 16) + ")").selectAll('rect').data(keyColors).enter().append('rect').attr('width', this.daySize).attr('height', this.daySize).attr('x', (function(_this) {
-        return function(color, i) {
-          return _this.daySizeWithSpace * i;
-        };
-      })(this)).attr('y', 0).attr('fill', function(color) {
-        return color;
-      });
+      const keyValues = ['no contributions', '1-9 contributions', '10-19 contributions', '20-29 contributions', '30+ contributions'];
+      const keyColors = ['#ededed', this.colorKey(0), this.colorKey(1), this.colorKey(2), this.colorKey(3)];
+
+      this.svg.append('g')
+        .attr('transform', `translate(18, ${this.daySizeWithSpace * 8 + 16})`)
+        .selectAll('rect')
+          .data(keyColors)
+          .enter()
+          .append('rect')
+            .attr('width', this.daySize)
+            .attr('height', this.daySize)
+            .attr('x', (color, i) => this.daySizeWithSpace * i)
+            .attr('y', 0)
+            .attr('fill', color => color)
+            .attr('class', 'js-tooltip')
+            .attr('title', (color, i) => keyValues[i])
+            .attr('data-container', 'body');
     };
 
     Calendar.prototype.initColor = function() {
diff --git a/app/assets/javascripts/users_select.js b/app/assets/javascripts/users_select.js
index 68cf9ced3ef..be29b08c343 100644
--- a/app/assets/javascripts/users_select.js
+++ b/app/assets/javascripts/users_select.js
@@ -1,6 +1,7 @@
 /* eslint-disable func-names, space-before-function-paren, one-var, no-var, prefer-rest-params, wrap-iife, quotes, max-len, one-var-declaration-per-line, vars-on-top, prefer-arrow-callback, consistent-return, comma-dangle, object-shorthand, no-shadow, no-unused-vars, no-else-return, no-self-compare, prefer-template, no-unused-expressions, no-lonely-if, yoda, prefer-spread, no-void, camelcase, no-param-reassign */
 /* global Issuable */
-/* global ListUser */
+
+import eventHub from './sidebar/event_hub';
 
 (function() {
   var bind = function(fn, me) { return function() { return fn.apply(me, arguments); }; },
@@ -54,42 +55,115 @@
           selectedIdDefault = (defaultNullUser && showNullUser) ? 0 : null;
           selectedId = $dropdown.data('selected') || selectedIdDefault;
 
-          var updateIssueBoardsIssue = function () {
-            $loading.removeClass('hidden').fadeIn();
-            gl.issueBoards.BoardsStore.detail.issue.update($dropdown.attr('data-issue-update'))
-              .then(function () {
-                $loading.fadeOut();
-              })
-              .catch(function () {
-                $loading.fadeOut();
-              });
+          const assignYourself = function () {
+            const unassignedSelected = $dropdown.closest('.selectbox')
+              .find(`input[name='${$dropdown.data('field-name')}'][value=0]`);
+
+            if (unassignedSelected) {
+              unassignedSelected.remove();
+            }
+
+            // Save current selected user to the DOM
+            const input = document.createElement('input');
+            input.type = 'hidden';
+            input.name = $dropdown.data('field-name');
+
+            const currentUserInfo = $dropdown.data('currentUserInfo');
+
+            if (currentUserInfo) {
+              input.value = currentUserInfo.id;
+              input.dataset.meta = currentUserInfo.name;
+            } else if (_this.currentUser) {
+              input.value = _this.currentUser.id;
+            }
+
+            if ($selectbox) {
+              $dropdown.parent().before(input);
+            } else {
+              $dropdown.after(input);
+            }
+          };
+
+          if ($block[0]) {
+            $block[0].addEventListener('assignYourself', assignYourself);
+          }
+
+          const getSelectedUserInputs = function() {
+            return $selectbox
+              .find(`input[name="${$dropdown.data('field-name')}"]`);
+          };
+
+          const getSelected = function() {
+            return getSelectedUserInputs()
+              .map((index, input) => parseInt(input.value, 10))
+              .get();
+          };
+
+          const checkMaxSelect = function() {
+            const maxSelect = $dropdown.data('max-select');
+            if (maxSelect) {
+              const selected = getSelected();
+
+              if (selected.length > maxSelect) {
+                const firstSelectedId = selected[0];
+                const firstSelected = $dropdown.closest('.selectbox')
+                  .find(`input[name='${$dropdown.data('field-name')}'][value=${firstSelectedId}]`);
+
+                firstSelected.remove();
+                eventHub.$emit('sidebar.removeAssignee', {
+                  id: firstSelectedId,
+                });
+              }
+            }
+          };
+
+          const getMultiSelectDropdownTitle = function(selectedUser, isSelected) {
+            const selectedUsers = getSelected()
+              .filter(u => u !== 0);
+
+            const firstUser = getSelectedUserInputs()
+              .map((index, input) => ({
+                name: input.dataset.meta,
+                value: parseInt(input.value, 10),
+              }))
+              .filter(u => u.id !== 0)
+              .get(0);
+
+            if (selectedUsers.length === 0) {
+              return 'Unassigned';
+            } else if (selectedUsers.length === 1) {
+              return firstUser.name;
+            } else if (isSelected) {
+              const otherSelected = selectedUsers.filter(s => s !== selectedUser.id);
+              return `${selectedUser.name} + ${otherSelected.length} more`;
+            } else {
+              return `${firstUser.name} + ${selectedUsers.length - 1} more`;
+            }
           };
 
           $('.assign-to-me-link').on('click', (e) => {
             e.preventDefault();
             $(e.currentTarget).hide();
-            const $input = $(`input[name="${$dropdown.data('field-name')}"]`);
-            $input.val(gon.current_user_id);
-            selectedId = $input.val();
-            $dropdown.find('.dropdown-toggle-text').text(gon.current_user_fullname).removeClass('is-default');
-          });
 
-          $block.on('click', '.js-assign-yourself', function(e) {
-            e.preventDefault();
-
-            if ($dropdown.hasClass('js-issue-board-sidebar')) {
-              gl.issueBoards.boardStoreIssueSet('assignee', new ListUser({
-                id: _this.currentUser.id,
-                username: _this.currentUser.username,
-                name: _this.currentUser.name,
-                avatar_url: _this.currentUser.avatar_url
-              }));
+            if ($dropdown.data('multiSelect')) {
+              assignYourself();
+              checkMaxSelect();
 
-              updateIssueBoardsIssue();
+              const currentUserInfo = $dropdown.data('currentUserInfo');
+              $dropdown.find('.dropdown-toggle-text').text(getMultiSelectDropdownTitle(currentUserInfo)).removeClass('is-default');
             } else {
-              return assignTo(_this.currentUser.id);
+              const $input = $(`input[name="${$dropdown.data('field-name')}"]`);
+              $input.val(gon.current_user_id);
+              selectedId = $input.val();
+              $dropdown.find('.dropdown-toggle-text').text(gon.current_user_fullname).removeClass('is-default');
             }
           });
+
+          $block.on('click', '.js-assign-yourself', (e) => {
+            e.preventDefault();
+            return assignTo(_this.currentUser.id);
+          });
+
           assignTo = function(selected) {
             var data;
             data = {};
@@ -97,6 +171,7 @@
             data[abilityName].assignee_id = selected != null ? selected : null;
             $loading.removeClass('hidden').fadeIn();
             $dropdown.trigger('loading.gl.dropdown');
+
             return $.ajax({
               type: 'PUT',
               dataType: 'json',
@@ -106,7 +181,6 @@
               var user;
               $dropdown.trigger('loaded.gl.dropdown');
               $loading.fadeOut();
-              $selectbox.hide();
               if (data.assignee) {
                 user = {
                   name: data.assignee.name,
@@ -133,51 +207,90 @@
               var isAuthorFilter;
               isAuthorFilter = $('.js-author-search');
               return _this.users(term, options, function(users) {
-                var anyUser, index, j, len, name, obj, showDivider;
-                if (term.length === 0) {
-                  showDivider = 0;
-                  if (firstUser) {
-                    // Move current user to the front of the list
-                    for (index = j = 0, len = users.length; j < len; index = (j += 1)) {
-                      obj = users[index];
-                      if (obj.username === firstUser) {
-                        users.splice(index, 1);
-                        users.unshift(obj);
-                        break;
-                      }
+                // GitLabDropdownFilter returns this.instance
+                // GitLabDropdownRemote returns this.options.instance
+                const glDropdown = this.instance || this.options.instance;
+                glDropdown.options.processData(term, users, callback);
+              }.bind(this));
+            },
+            processData: function(term, users, callback) {
+              let anyUser;
+              let index;
+              let j;
+              let len;
+              let name;
+              let obj;
+              let showDivider;
+              if (term.length === 0) {
+                showDivider = 0;
+                if (firstUser) {
+                  // Move current user to the front of the list
+                  for (index = j = 0, len = users.length; j < len; index = (j += 1)) {
+                    obj = users[index];
+                    if (obj.username === firstUser) {
+                      users.splice(index, 1);
+                      users.unshift(obj);
+                      break;
                     }
                   }
-                  if (showNullUser) {
-                    showDivider += 1;
-                    users.unshift({
-                      beforeDivider: true,
-                      name: 'Unassigned',
-                      id: 0
-                    });
-                  }
-                  if (showAnyUser) {
-                    showDivider += 1;
-                    name = showAnyUser;
-                    if (name === true) {
-                      name = 'Any User';
-                    }
-                    anyUser = {
-                      beforeDivider: true,
-                      name: name,
-                      id: null
-                    };
-                    users.unshift(anyUser);
+                }
+                if (showNullUser) {
+                  showDivider += 1;
+                  users.unshift({
+                    beforeDivider: true,
+                    name: 'Unassigned',
+                    id: 0
+                  });
+                }
+                if (showAnyUser) {
+                  showDivider += 1;
+                  name = showAnyUser;
+                  if (name === true) {
+                    name = 'Any User';
                   }
+                  anyUser = {
+                    beforeDivider: true,
+                    name: name,
+                    id: null
+                  };
+                  users.unshift(anyUser);
                 }
+
                 if (showDivider) {
-                  users.splice(showDivider, 0, "divider");
+                  users.splice(showDivider, 0, 'divider');
                 }
 
-                callback(users);
-                if (showMenuAbove) {
-                  $dropdown.data('glDropdown').positionMenuAbove();
+                if ($dropdown.hasClass('js-multiselect')) {
+                  const selected = getSelected().filter(i => i !== 0);
+
+                  if (selected.length > 0) {
+                    if ($dropdown.data('dropdown-header')) {
+                      showDivider += 1;
+                      users.splice(showDivider, 0, {
+                        header: $dropdown.data('dropdown-header'),
+                      });
+                    }
+
+                    const selectedUsers = users
+                      .filter(u => selected.indexOf(u.id) !== -1)
+                      .sort((a, b) => a.name > b.name);
+
+                    users = users.filter(u => selected.indexOf(u.id) === -1);
+
+                    selectedUsers.forEach((selectedUser) => {
+                      showDivider += 1;
+                      users.splice(showDivider, 0, selectedUser);
+                    });
+
+                    users.splice(showDivider + 1, 0, 'divider');
+                  }
                 }
-              });
+              }
+
+              callback(users);
+              if (showMenuAbove) {
+                $dropdown.data('glDropdown').positionMenuAbove();
+              }
             },
             filterable: true,
             filterRemote: true,
@@ -186,7 +299,22 @@
             },
             selectable: true,
             fieldName: $dropdown.data('field-name'),
-            toggleLabel: function(selected, el) {
+            toggleLabel: function(selected, el, glDropdown) {
+              const inputValue = glDropdown.filterInput.val();
+
+              if (this.multiSelect && inputValue === '') {
+                // Remove non-users from the fullData array
+                const users = glDropdown.filteredFullData();
+                const callback = glDropdown.parseData.bind(glDropdown);
+
+                // Update the data model
+                this.processData(inputValue, users, callback);
+              }
+
+              if (this.multiSelect) {
+                return getMultiSelectDropdownTitle(selected, $(el).hasClass('is-active'));
+              }
+
               if (selected && 'id' in selected && $(el).hasClass('is-active')) {
                 $dropdown.find('.dropdown-toggle-text').removeClass('is-default');
                 if (selected.text) {
@@ -200,22 +328,81 @@
               }
             },
             defaultLabel: defaultLabel,
-            inputId: 'issue_assignee_id',
             hidden: function(e) {
-              $selectbox.hide();
-              // display:block overrides the hide-collapse rule
-              return $value.css('display', '');
+              if ($dropdown.hasClass('js-multiselect')) {
+                eventHub.$emit('sidebar.saveAssignees');
+              }
+
+              if (!$dropdown.data('always-show-selectbox')) {
+                $selectbox.hide();
+
+                // Recalculate where .value is because vue might have changed it
+                $block = $selectbox.closest('.block');
+                $value = $block.find('.value');
+                // display:block overrides the hide-collapse rule
+                $value.css('display', '');
+              }
             },
-            vue: $dropdown.hasClass('js-issue-board-sidebar'),
-            clicked: function(user, $el, e) {
-              var isIssueIndex, isMRIndex, page, selected, isSelecting;
+            multiSelect: $dropdown.hasClass('js-multiselect'),
+            inputMeta: $dropdown.data('input-meta'),
+            clicked: function(options) {
+              const { $el, e, isMarking } = options;
+              const user = options.selectedObj;
+
+              if ($dropdown.hasClass('js-multiselect')) {
+                const isActive = $el.hasClass('is-active');
+                const previouslySelected = $dropdown.closest('.selectbox')
+                    .find("input[name='" + ($dropdown.data('field-name')) + "'][value!=0]");
+
+                // Enables support for limiting the number of users selected
+                // Automatically removes the first on the list if more users are selected
+                checkMaxSelect();
+
+                if (user.beforeDivider && user.name.toLowerCase() === 'unassigned') {
+                  // Unassigned selected
+                  previouslySelected.each((index, element) => {
+                    const id = parseInt(element.value, 10);
+                    element.remove();
+                  });
+                  eventHub.$emit('sidebar.removeAllAssignees');
+                } else if (isActive) {
+                  // user selected
+                  eventHub.$emit('sidebar.addAssignee', user);
+
+                  // Remove unassigned selection (if it was previously selected)
+                  const unassignedSelected = $dropdown.closest('.selectbox')
+                    .find("input[name='" + ($dropdown.data('field-name')) + "'][value=0]");
+
+                  if (unassignedSelected) {
+                    unassignedSelected.remove();
+                  }
+                } else {
+                  if (previouslySelected.length === 0) {
+                  // Select unassigned because there is no more selected users
+                    this.addInput($dropdown.data('field-name'), 0, {});
+                  }
+
+                  // User unselected
+                  eventHub.$emit('sidebar.removeAssignee', user);
+                }
+
+                if (getSelected().find(u => u === gon.current_user_id)) {
+                  $('.assign-to-me-link').hide();
+                } else {
+                  $('.assign-to-me-link').show();
+                }
+              }
+
+              var isIssueIndex, isMRIndex, page, selected;
               page = $('body').data('page');
               isIssueIndex = page === 'projects:issues:index';
               isMRIndex = (page === page && page === 'projects:merge_requests:index');
-              isSelecting = (user.id !== selectedId);
-              selectedId = isSelecting ? user.id : selectedIdDefault;
               if ($dropdown.hasClass('js-filter-bulk-update') || $dropdown.hasClass('js-issuable-form-dropdown')) {
                 e.preventDefault();
+
+                const isSelecting = (user.id !== selectedId);
+                selectedId = isSelecting ? user.id : selectedIdDefault;
+
                 if (selectedId === gon.current_user_id) {
                   $('.assign-to-me-link').hide();
                 } else {
@@ -229,20 +416,7 @@
                 return Issuable.filterResults($dropdown.closest('form'));
               } else if ($dropdown.hasClass('js-filter-submit')) {
                 return $dropdown.closest('form').submit();
-              } else if ($dropdown.hasClass('js-issue-board-sidebar')) {
-                if (user.id && isSelecting) {
-                  gl.issueBoards.boardStoreIssueSet('assignee', new ListUser({
-                    id: user.id,
-                    username: user.username,
-                    name: user.name,
-                    avatar_url: user.avatar_url
-                  }));
-                } else {
-                  gl.issueBoards.boardStoreIssueDelete('assignee');
-                }
-
-                updateIssueBoardsIssue();
-              } else {
+              } else if (!$dropdown.hasClass('js-multiselect')) {
                 selected = $dropdown.closest('.selectbox').find("input[name='" + ($dropdown.data('field-name')) + "']").val();
                 return assignTo(selected);
               }
@@ -256,29 +430,54 @@
                 selectedId = parseInt($dropdown[0].dataset.selected, 10) || selectedIdDefault;
               }
               $el.find('.is-active').removeClass('is-active');
-              $el.find(`li[data-user-id="${selectedId}"] .dropdown-menu-user-link`).addClass('is-active');
+
+              function highlightSelected(id) {
+                $el.find(`li[data-user-id="${id}"] .dropdown-menu-user-link`).addClass('is-active');
+              }
+
+              if ($selectbox[0]) {
+                getSelected().forEach(selectedId => highlightSelected(selectedId));
+              } else {
+                highlightSelected(selectedId);
+              }
             },
+            updateLabel: $dropdown.data('dropdown-title'),
             renderRow: function(user) {
-              var avatar, img, listClosingTags, listWithName, listWithUserName, selected, username;
+              var avatar, img, listClosingTags, listWithName, listWithUserName, username;
               username = user.username ? "@" + user.username : "";
               avatar = user.avatar_url ? user.avatar_url : false;
-              selected = user.id === parseInt(selectedId, 10) ? "is-active" : "";
+
+              let selected = user.id === parseInt(selectedId, 10);
+
+              if (this.multiSelect) {
+                const fieldName = this.fieldName;
+                const field = $dropdown.closest('.selectbox').find("input[name='" + fieldName + "'][value='" + user.id + "']");
+
+                if (field.length) {
+                  selected = true;
+                }
+              }
+
               img = "";
               if (user.beforeDivider != null) {
-                "<li> <a href='#' class='" + selected + "'> " + user.name + " </a> </li>";
+                `<li><a href='#' class='${selected === true ? 'is-active' : ''}'>${user.name}</a></li>`;
               } else {
                 if (avatar) {
-                  img = "<img src='" + avatar + "' class='avatar avatar-inline' width='30' />";
+                  img = "<img src='" + avatar + "' class='avatar avatar-inline' width='32' />";
                 }
               }
-              // split into three parts so we can remove the username section if nessesary
-              listWithName = "<li data-user-id=" + user.id + "> <a href='#' class='dropdown-menu-user-link " + selected + "'> " + img + " <strong class='dropdown-menu-user-full-name'> " + user.name + " </strong>";
-              listWithUserName = "<span class='dropdown-menu-user-username'> " + username + " </span>";
-              listClosingTags = "</a> </li>";
-              if (username === '') {
-                listWithUserName = '';
-              }
-              return listWithName + listWithUserName + listClosingTags;
+
+              return `
+                <li data-user-id=${user.id}>
+                  <a href='#' class='dropdown-menu-user-link ${selected === true ? 'is-active' : ''}'>
+                    ${img}
+                    <strong class='dropdown-menu-user-full-name'>
+                      ${user.name}
+                    </strong>
+                    ${username ? `<span class='dropdown-menu-user-username'>${username}</span>` : ''}
+                  </a>
+                </li>
+              `;
             }
           });
         };