whitelist style attribute in event_note

app/helpers/events_helper.rb

@@ -162,7 +162,12 @@ module EventsHelper
   def event_note(text, options = {})
     text = first_line_in_markdown(text, 150, options)
-    sanitize(text, tags: %w(a img b pre code p span))
+
+    sanitize(
+      text,
+      tags: %w(a img b pre code p span),
+      attributes: Rails::Html::WhiteListSanitizer.allowed_attributes + ['style']
+    )
   end
   def event_commit_title(message)

changelogs/unreleased/26790-label-color-todos.yml

+---
+title: fix background color for labels mention in todo
+merge_request: 9155
+author: mhasbini

spec/helpers/events_helper_spec.rb

@@ -61,6 +61,13 @@ describe EventsHelper do
         '</code></pre>'
       expect(helper.event_note(input)).to eq(expected)
     end
+
+    it 'preserves style attribute within a tag' do
+      input = '<span class="" style="background-color: #44ad8e; color: #FFFFFF;"></span>'
+      expected = '<p><span style="background-color: #44ad8e; color: #FFFFFF;"></span></p>'
+
+      expect(helper.event_note(input)).to eq(expected)
+    end
   end
   describe '#event_commit_title' do