diff --git a/locales/index.d.ts b/locales/index.d.ts
index 90825836cb..fd9a2cb7e0 100644
--- a/locales/index.d.ts
+++ b/locales/index.d.ts
@@ -462,6 +462,8 @@ export interface Locale {
     "next": string;
     "retype": string;
     "noteOf": string;
+    "expandAllCws": string;
+    "collapseAllCws": string;
     "quoteAttached": string;
     "quoteQuestion": string;
     "noMessagesYet": string;
diff --git a/locales/ja-JP.yml b/locales/ja-JP.yml
index 8433313cad..deab375c1a 100644
--- a/locales/ja-JP.yml
+++ b/locales/ja-JP.yml
@@ -459,6 +459,8 @@ enable: "有効にする"
 next: "次"
 retype: "再入力"
 noteOf: "{user}のノート"
+expandAllCws: "すべての返信の内容を表示する"
+collapseAllCws: "すべての返信の内容を隠す"
 quoteAttached: "引用付き"
 quoteQuestion: "引用として添付しますか？"
 noMessagesYet: "まだチャットはありません"