diff --git a/spec/features/merge_requests/deleted_source_branch_spec.rb b/spec/features/merge_requests/deleted_source_branch_spec.rb
index 778b3a90cf307d6a87a439dd0a17468c8aacea7b..d5c9ed8a3b7fe863f7cabc83dddcccd1f7bfc76e 100644
--- a/spec/features/merge_requests/deleted_source_branch_spec.rb
+++ b/spec/features/merge_requests/deleted_source_branch_spec.rb
@@ -1,5 +1,8 @@
 require 'spec_helper'
 
+# This test serves as a regression test for a bug that caused an error
+# message to be shown by JavaScript when the source branch was deleted.
+# Please do not remove "js: true".
 describe 'Deleted source branch', feature: true, js: true do
   let(:user) { create(:user) }
   let(:merge_request) { create(:merge_request) }