diff --git a/CHANGELOG b/CHANGELOG
index 2f71891a7ba..996a5bf8697 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -11,6 +11,7 @@ v 7.4.0
   - Prevent notes polling when there are not notes
   - API: Add support for forking a project via the API (Bernhard Kaindl)
   - API: filter project issues by milestone (Julien Bianchi)
+  - Zen mode for wiki and milestones (Robert Schilling)
 
 v 7.3.2
   - Fix creating new file via web editor
diff --git a/app/assets/javascripts/dispatcher.js.coffee b/app/assets/javascripts/dispatcher.js.coffee
index 086c09f196e..00b52758fa8 100644
--- a/app/assets/javascripts/dispatcher.js.coffee
+++ b/app/assets/javascripts/dispatcher.js.coffee
@@ -27,6 +27,8 @@ class Dispatcher
         new ZenMode()
       when 'projects:milestones:show'
         new Milestone()
+      when 'projects:milestones:new'
+        new ZenMode()
       when 'projects:issues:new','projects:issues:edit'
         GitLab.GfmAutoComplete.setup()
         shortcut_handler = new ShortcutsNavigation()
@@ -87,6 +89,7 @@ class Dispatcher
           when 'wikis'
             new Wikis()
             shortcut_handler = new ShortcutsNavigation()
+            new ZenMode()
           when 'snippets', 'labels', 'graphs'
             shortcut_handler = new ShortcutsNavigation()
           when 'team_members', 'deploy_keys', 'hooks', 'services', 'protected_branches'
diff --git a/app/assets/stylesheets/generic/gfm.scss b/app/assets/stylesheets/generic/gfm.scss
new file mode 100644
index 00000000000..e257f053618
--- /dev/null
+++ b/app/assets/stylesheets/generic/gfm.scss
@@ -0,0 +1,20 @@
+/**
+ * Styles that apply to all GFM related forms.
+ */
+.issue-form, .merge-request-form, .wiki-form {
+  .description {
+    height: 20em;
+  }
+}
+
+.wiki-form {
+  .description {
+    height: 26em;
+  }
+}
+
+.milestone-form {
+  .description {
+    height: 14em;
+  }
+}
\ No newline at end of file
diff --git a/app/assets/stylesheets/generic/issuable.scss b/app/assets/stylesheets/generic/issuable.scss
deleted file mode 100644
index f456b3ace1a..00000000000
--- a/app/assets/stylesheets/generic/issuable.scss
+++ /dev/null
@@ -1,9 +0,0 @@
-/**
- * Styles that apply to both issues and merge requests.
- */
-
-.issue-form, .merge-request-form {
-  .description {
-    height: 20em;
-  }
-}
diff --git a/app/views/projects/milestones/_form.html.haml b/app/views/projects/milestones/_form.html.haml
index 27069802d5a..5fb01a11cc5 100644
--- a/app/views/projects/milestones/_form.html.haml
+++ b/app/views/projects/milestones/_form.html.haml
@@ -5,7 +5,7 @@
 
 %hr
 
-= form_for [@project, @milestone], html: {class: "new_milestone form-horizontal gfm-form"}  do |f|
+= form_for [@project, @milestone], html: {class: 'form-horizontal milestone-form gfm-form'}  do |f|
   -if @milestone.errors.any?
     .alert.alert-danger
       %ul
@@ -21,7 +21,7 @@
       .form-group
         = f.label :description, "Description", class: "control-label"
         .col-sm-10
-          = f.text_area :description, maxlength: 65535, class: "form-control markdown-area", rows: 10
+          = render 'projects/zen', f: f, attr: :description, classes: 'description form-control'
           .hint
             .pull-left Milestones are parsed with #{link_to "GitLab Flavored Markdown", help_page_path("markdown", "markdown"), target: '_blank'}.
             .pull-left Attach images (JPG, PNG, GIF) by dragging & dropping or #{link_to "selecting them", '#', class: 'markdown-selector' }.
diff --git a/app/views/projects/wikis/_form.html.haml b/app/views/projects/wikis/_form.html.haml
index 1e39e4dd774..f37c086716d 100644
--- a/app/views/projects/wikis/_form.html.haml
+++ b/app/views/projects/wikis/_form.html.haml
@@ -1,4 +1,4 @@
-= form_for [@project, @page], method: @page.persisted? ? :put : :post, html: { class: 'form-horizontal gfm-form' } do |f|
+= form_for [@project, @page], method: @page.persisted? ? :put : :post, html: { class: 'form-horizontal wiki-form gfm-form' } do |f|
   -if @page.errors.any?
     #error_explanation
       .alert.alert-danger
@@ -22,7 +22,7 @@
   .form-group
     = f.label :content, class: 'control-label'
     .col-sm-10
-      = f.text_area :content, class: 'form-control js-gfm-input markdown-area', rows: 18
+      = render 'projects/zen', f: f, attr: :content, classes: 'description form-control'
       .col-sm-12.hint
         .pull-left Wiki content is parsed with #{link_to "GitLab Flavored Markdown", help_page_path("markdown", "markdown"), target: '_blank'}
         .pull-right Attach images (JPG, PNG, GIF) by dragging & dropping or #{link_to "selecting them", '#', class: 'markdown-selector' }.