diff --git a/ext/js/pages/settings/dictionary-controller.js b/ext/js/pages/settings/dictionary-controller.js
index 33bc9d7b7..2d5a942f7 100644
--- a/ext/js/pages/settings/dictionary-controller.js
+++ b/ext/js/pages/settings/dictionary-controller.js
@@ -832,9 +832,7 @@ export class DictionaryController {
         const dictionaries = this._dictionaries;
         if (dictionaries === null) { return; }
 
-        for (const entry of this._dictionaryEntries) {
-            entry.cleanup();
-        }
+        this._dictionaryEntries.map((dictionaryEntry) => dictionaryEntry.cleanup());
 
         const dictionaryOptionsArray = options.dictionaries;
         for (let i = 0, ii = dictionaryOptionsArray.length; i < ii; ++i) {