diff --git a/extensions/mentions/js/src/mentioned-by-list.js b/extensions/mentions/js/src/mentioned-by-list.js
index 12a9ac5f7..62ef840ec 100644
--- a/extensions/mentions/js/src/mentioned-by-list.js
+++ b/extensions/mentions/js/src/mentioned-by-list.js
@@ -5,6 +5,7 @@ import DiscussionPage from 'flarum/components/discussion-page';
 import PostComment from 'flarum/components/post-comment';
 import PostPreview from 'flarum/components/post-preview';
 import punctuate from 'flarum/helpers/punctuate';
+import username from 'flarum/helpers/username';
 
 export default function mentionedByList() {
   Post.prototype.mentionedBy = Model.many('mentionedBy');