Resolve difference in app/assets/stylesheets/application.scss

app/assets/stylesheets/_ee/application_ee.scss

+/*
+ This is a noop-file. In EE:
+ ee/app/assets/stylesheets/_ee/application_ee.scss
+ will take precedence over it and import more styles
+ */

app/assets/stylesheets/application.scss

@@ -34,4 +34,8 @@
 // Styles for JS behaviors.
 @import "behaviors";
+// EE-only stylesheets
+@import "application_ee";
+
+// CSS util classes
 @import "utilities";

config/application.rb

@@ -183,6 +183,12 @@ module Gitlab
       config.assets.precompile << "pages/jira_connect.css"
     end
+    # Import path for EE specific SCSS entry point
+    # In CE it will import a noop file, in EE a functioning file
+    # Order is important, so that the ee file takes precedence:
+    config.assets.paths << "#{config.root}/ee/app/assets/stylesheets/_ee"
+    config.assets.paths << "#{config.root}/app/assets/stylesheets/_ee"
+
     config.assets.paths << "#{config.root}/vendor/assets/javascripts/"
     config.assets.precompile << "snowplow/sp.js"