diff --git a/frontend/src/i18n/ja.json b/frontend/src/i18n/ja.json
index 574bf59a..0e6b9c04 100644
--- a/frontend/src/i18n/ja.json
+++ b/frontend/src/i18n/ja.json
@@ -158,6 +158,7 @@
     "video": "動画"
   },
   "settings": {
+    "aceEditorTheme": "Ace editor theme",
     "admin": "管理者",
     "administrator": "管理者",
     "allowCommands": "コマンドの実行",