diff --git a/packages/backend/src/misc/get-note-summary.ts b/packages/backend/src/misc/get-note-summary.ts
index 079eda6fbb..be183b4979 100644
--- a/packages/backend/src/misc/get-note-summary.ts
+++ b/packages/backend/src/misc/get-note-summary.ts
@@ -3,6 +3,7 @@
  * SPDX-License-Identifier: AGPL-3.0-only
  */
 
+import { appendContentWarning } from './append-content-warning.js';
 import type { Packed } from './json-schema.js';
 
 /**
@@ -23,16 +24,16 @@ export const getNoteSummary = (note: Packed<'Note'>): string => {
 	// Append mandatory CW, if applicable
 	let cw = note.cw;
 	if (note.mandatoryCW) {
-		cw = `Note is flagged: "${note.mandatoryCW}", ${cw}`;
+		cw = appendContentWarning(cw, `Note is flagged: "${note.mandatoryCW}"`);
 	}
 	if (note.user.mandatoryCW) {
 		const username = note.user.host
 			? `@${note.user.username}@${note.user.host}`
 			: `@${note.user.username}`;
-		cw = `${username} is flagged: "${note.user.mandatoryCW}", ${cw}`;
+		cw = appendContentWarning(cw, `${username} is flagged: "${note.user.mandatoryCW}"`);
 	}
 	if (note.user.instance?.mandatoryCW) {
-		cw = `${note.user.host} is flagged: "${note.user.instance.mandatoryCW}", ${cw}`;
+		cw = appendContentWarning(cw, `${note.user.host} is flagged: "${note.user.instance.mandatoryCW}"`);
 	}
 
 	// 本文
diff --git a/packages/frontend/src/utility/get-note-summary.ts b/packages/frontend/src/utility/get-note-summary.ts
index f96f75b8a9..35da364c11 100644
--- a/packages/frontend/src/utility/get-note-summary.ts
+++ b/packages/frontend/src/utility/get-note-summary.ts
@@ -4,6 +4,7 @@
  */
 
 import * as Misskey from 'misskey-js';
+import { appendContentWarning } from '@@/js/append-content-warning.js';
 import { host } from '@@/js/config.js';
 import { i18n } from '@/i18n.js';
 
@@ -31,17 +32,17 @@ export const getNoteSummary = (note: Misskey.entities.Note | null | undefined, w
 	let cw = note.cw;
 	if (withMandatoryCw) {
 		if (note.mandatoryCW) {
-			cw = i18n.tsx.noteIsFlaggedAs({ cw: note.mandatoryCW }) + ', ' + cw;
+			cw = appendContentWarning(cw, i18n.tsx.noteIsFlaggedAs({ cw: note.mandatoryCW }));
 		}
 		if (note.user.mandatoryCW) {
 			const username = note.user.host
 				? `@${note.user.username}@${note.user.host}`
 				: `@${note.user.username}`;
-			cw = i18n.tsx.userIsFlaggedAs({ name: username, cw: note.user.mandatoryCW }) + ', ' + cw;
+			cw = appendContentWarning(cw, i18n.tsx.userIsFlaggedAs({ name: username, cw: note.user.mandatoryCW }));
 		}
 		if (note.user.instance?.mandatoryCW) {
 			const instanceName = note.user.host ?? host;
-			cw = i18n.tsx.instanceIsFlaggedAs({ name: instanceName, cw: note.user.instance.mandatoryCW }) + ', ' + cw;
+			cw = appendContentWarning(cw, i18n.tsx.instanceIsFlaggedAs({ name: instanceName, cw: note.user.instance.mandatoryCW }));
 		}
 	}