diff --git a/.rubocop_todo.yml b/.rubocop_todo.yml
index e8f8fac73..f72a651c3 100644
--- a/.rubocop_todo.yml
+++ b/.rubocop_todo.yml
@@ -477,7 +477,6 @@ Layout/SpaceInsidePercentLiteralDelimiters:
 Layout/SpaceInsideStringInterpolation:
   Exclude:
     - 'app/helpers/application_helper.rb'
-    - 'app/helpers/issues_helper.rb'
     - 'app/helpers/workflows_helper.rb'
     - 'app/models/issue_query.rb'
     - 'app/models/mail_handler.rb'
diff --git a/app/helpers/issues_helper.rb b/app/helpers/issues_helper.rb
index df777d7e2..deb5b7518 100644
--- a/app/helpers/issues_helper.rb
+++ b/app/helpers/issues_helper.rb
@@ -515,7 +515,7 @@ module IssuesHelper
         diff_link = link_to 'diff',
           diff_journal_url(detail.journal_id, :detail_id => detail.id, :only_path => options[:only_path]),
           :title => l(:label_view_diff)
-        s << " (#{ diff_link })"
+        s << " (#{diff_link})"
       end
       s.html_safe
     elsif detail.value.present?