diff --git a/app/helpers/application_helper.rb b/app/helpers/application_helper.rb
index 0ca9345f5b..022933ac47 100644
--- a/app/helpers/application_helper.rb
+++ b/app/helpers/application_helper.rb
@@ -993,7 +993,12 @@ module ApplicationHelper
       I18n.locale = "#{I18n.locale}";
     })
     unless User.current.pref.warn_on_leaving_unsaved == '0'
-      tags += javascript_tag("jQuery(function(){ new WarnLeavingUnsaved('#{escape_javascript( l(:text_warn_on_leaving_unsaved) )}'); });")
+      tags += javascript_tag("jQuery(document).ready(function(){
+                                new WarnLeavingUnsaved('#{escape_javascript( l(:text_warn_on_leaving_unsaved) )}');
+                                jQuery(document).ajaxComplete(function(){
+                                    new WarnLeavingUnsaved('#{escape_javascript( l(:text_warn_on_leaving_unsaved) )}')
+                                });
+                            })")
     end
 
     if User.current.impaired? and accessibility_js_enabled?
diff --git a/features/work_packages/attachments.feature b/features/work_packages/attachments.feature
index 75ffdbfca0..59d9f7acad 100644
--- a/features/work_packages/attachments.feature
+++ b/features/work_packages/attachments.feature
@@ -43,6 +43,8 @@ Feature: Attachments on work packages
       | edit_work_packages |
     And there is 1 user with the following:
       | login | bob|
+    And the user "bob" has the following preferences
+      | warn_on_leaving_unsaved | 0 |
     And the user "bob" is a "member" in the project "parent"
     And there are the following issue status:
       | name        | is_closed | is_default |