diff --git a/packages/backend/src/@types/twemoji.d.ts b/packages/backend/src/@types/twemoji.d.ts
index 8574f103ed..deefab6d44 100644
--- a/packages/backend/src/@types/twemoji.d.ts
+++ b/packages/backend/src/@types/twemoji.d.ts
@@ -3,7 +3,7 @@
  * SPDX-License-Identifier: AGPL-3.0-only
  */
 
-declare module '@twemoji/parser/dist/lib/regex' {
+declare module '@twemoji/parser/dist/lib/regex.js' {
 	const regex: RegExp;
 	export default { default: regex };
 }
diff --git a/packages/backend/src/core/MfmService.ts b/packages/backend/src/core/MfmService.ts
index 90a657b484..9ed160b8d3 100644
--- a/packages/backend/src/core/MfmService.ts
+++ b/packages/backend/src/core/MfmService.ts
@@ -7,7 +7,7 @@ import { URL } from 'node:url';
 import { Inject, Injectable } from '@nestjs/common';
 import * as parse5 from 'parse5';
 import { Window, XMLSerializer } from 'happy-dom';
-import twemojiRegex from '@twemoji/parser/dist/lib/regex';
+import twemojiRegex from '@twemoji/parser/dist/lib/regex.js';
 import { DI } from '@/di-symbols.js';
 import type { Config } from '@/config.js';
 import { intersperse } from '@/misc/prelude/array.js';