diff --git a/CHANGELOG b/CHANGELOG
index ecce18af066..6d5663134d5 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -43,6 +43,7 @@ v 8.8.4 (unreleased)
   - Fix issue with arrow keys not working in search autocomplete dropdown
   - Fix todos page throwing errors when you have a project pending deletion
   - Reduce number of SQL queries when rendering user references
+  - Upgrade to jQuery 2
 
 v 8.8.3
   - Fix 404 page when viewing TODOs that contain milestones or labels in different projects. !4312
diff --git a/app/assets/javascripts/due_date_select.js.coffee b/app/assets/javascripts/due_date_select.js.coffee
index 3cc70185178..3d009a96d05 100644
--- a/app/assets/javascripts/due_date_select.js.coffee
+++ b/app/assets/javascripts/due_date_select.js.coffee
@@ -21,7 +21,7 @@ class @DueDateSelect
       $dropdown.glDropdown(
         hidden: ->
           $selectbox.hide()
-          $value.removeAttr('style')
+          $value.css('display', '')
       )
 
       addDueDate = (isDropdown) ->
@@ -42,12 +42,13 @@ class @DueDateSelect
           type: 'PUT'
           url: issueUpdateURL
           data: data
+          dataType: 'json'
           beforeSend: ->
             $loading.fadeIn()
             if isDropdown
               $dropdown.trigger('loading.gl.dropdown')
               $selectbox.hide()
-            $value.removeAttr('style')
+            $value.css('display', '')
 
             $valueContent.html(mediumDate)
             $sidebarValue.html(mediumDate)
diff --git a/app/assets/javascripts/milestone_select.js.coffee b/app/assets/javascripts/milestone_select.js.coffee
index 345a0e447af..1d061d5edb7 100644
--- a/app/assets/javascripts/milestone_select.js.coffee
+++ b/app/assets/javascripts/milestone_select.js.coffee
@@ -83,7 +83,7 @@ class @MilestoneSelect
           $selectbox.hide()
 
           # display:block overrides the hide-collapse rule
-          $value.removeAttr('style')
+          $value.css('display', '')
         clicked: (selected) ->
           page = $('body').data 'page'
           isIssueIndex = page is 'projects:issues:index'
@@ -118,7 +118,7 @@ class @MilestoneSelect
               $dropdown.trigger('loaded.gl.dropdown')
               $loading.fadeOut()
               $selectbox.hide()
-              $value.removeAttr('style')
+              $value.css('display', '')
               if data.milestone?
                 data.milestone.namespace = _this.currentProject.namespace
                 data.milestone.path = _this.currentProject.path
diff --git a/app/assets/javascripts/users_select.js.coffee b/app/assets/javascripts/users_select.js.coffee
index 519618aa617..de0eae58bff 100644
--- a/app/assets/javascripts/users_select.js.coffee
+++ b/app/assets/javascripts/users_select.js.coffee
@@ -149,7 +149,7 @@ class @UsersSelect
         hidden: (e) ->
           $selectbox.hide()
           # display:block overrides the hide-collapse rule
-          $value.removeAttr('style')
+          $value.css('display', '')
 
         clicked: (user) ->
           page = $('body').data 'page'
diff --git a/spec/features/issues_spec.rb b/spec/features/issues_spec.rb
index a4eed5031c9..460d7f82b36 100644
--- a/spec/features/issues_spec.rb
+++ b/spec/features/issues_spec.rb
@@ -365,13 +365,9 @@ describe 'Issues', feature: true do
 
         page.within('.assignee') do
           expect(page).to have_content "#{@user.name}"
-        end
 
-        find('.block.assignee .edit-link').click
-        sleep 2 # wait for ajax stuff to complete
-        first('.dropdown-menu-user-link').click
-        sleep 2
-        page.within('.assignee') do
+          click_link 'Edit'
+          click_link 'Unassigned'
           expect(page).to have_content 'No assignee'
         end
 
diff --git a/spec/javascripts/graphs/stat_graph_contributors_util_spec.js b/spec/javascripts/graphs/stat_graph_contributors_util_spec.js
index 5b992447473..56970e22e34 100644
--- a/spec/javascripts/graphs/stat_graph_contributors_util_spec.js
+++ b/spec/javascripts/graphs/stat_graph_contributors_util_spec.js
@@ -9,14 +9,14 @@ describe("ContributorsStatGraphUtil", function () {
             {author_email: "dzaporozhets@email.com", author_name: "Dmitriy Zaporozhets", date: "2013-05-08", additions: 6, deletions: 1},
             {author_email: "dzaporozhets@email.com", author_name: "Dmitriy Zaporozhets", date: "2013-05-08", additions: 19, deletions: 3},
             {author_email: "dzaporozhets@email.com", author_name: "Dmitriy Zaporozhets", date: "2013-05-08", additions: 29, deletions: 3}]
-      
+
       var correct_parsed_log = {
         total: [
         {date: "2013-05-09", additions: 471, deletions: 0, commits: 1},
         {date: "2013-05-08", additions: 54, deletions: 7, commits: 3}],
         by_author:
         [
-        { 
+        {
           author_name: "Karlo Soriano", author_email: "karlo@email.com",
           "2013-05-09": {date: "2013-05-09", additions: 471, deletions: 0, commits: 1}
         },
@@ -132,8 +132,8 @@ describe("ContributorsStatGraphUtil", function () {
       total: [{date: "2013-05-09", additions: 471, deletions: 0, commits: 1},
       {date: "2013-05-08", additions: 54, deletions: 7, commits: 3}],
       by_author:[
-      { 
-        author: "Karlo Soriano", 
+      {
+        author: "Karlo Soriano",
         "2013-05-09": {date: "2013-05-09", additions: 471, deletions: 0, commits: 1}
       },
       {
@@ -161,11 +161,11 @@ describe("ContributorsStatGraphUtil", function () {
     it("returns the log by author sorted by specified field", function () {
       var fake_parsed_log = {
         total: [
-          {date: "2013-05-09", additions: 471, deletions: 0, commits: 1}, 
+          {date: "2013-05-09", additions: 471, deletions: 0, commits: 1},
           {date: "2013-05-08", additions: 54, deletions: 7, commits: 3}
         ],
         by_author: [
-          { 
+          {
             author_name: "Karlo Soriano", author_email: "karlo@email.com",
             "2013-05-09": {date: "2013-05-09", additions: 471, deletions: 0, commits: 1}
           },