diff --git a/.rubocop_todo.yml b/.rubocop_todo.yml
index 674f50920..38ddef746 100644
--- a/.rubocop_todo.yml
+++ b/.rubocop_todo.yml
@@ -1482,7 +1482,6 @@ Style/WhileUntilModifier:
     - 'app/helpers/queries_helper.rb'
     - 'app/models/attachment.rb'
     - 'app/models/project.rb'
-    - 'lib/redmine/export/pdf/issues_pdf_helper.rb'
     - 'lib/redmine/unified_diff.rb'
     - 'lib/redmine/utils.rb'
     - 'lib/redmine/wiki_formatting/textile/redcloth3.rb'
diff --git a/lib/redmine/export/pdf/issues_pdf_helper.rb b/lib/redmine/export/pdf/issues_pdf_helper.rb
index 8b1e59ae2..41a9b0c19 100644
--- a/lib/redmine/export/pdf/issues_pdf_helper.rb
+++ b/lib/redmine/export/pdf/issues_pdf_helper.rb
@@ -61,12 +61,8 @@ module Redmine
           right << [l(:label_spent_time), l_hours(issue.total_spent_hours)] if User.current.allowed_to?(:view_time_entries, issue.project)
 
           rows = left.size > right.size ? left.size : right.size
-          while left.size < rows
-            left << nil
-          end
-          while right.size < rows
-            right << nil
-          end
+          left  << nil while left.size  < rows
+          right << nil while right.size < rows
 
           custom_field_values = issue.visible_custom_field_values.reject {|value| value.custom_field.full_width_layout?}
           half = (custom_field_values.size / 2.0).ceil