diff --git a/packages/backend/test/resources/hw.png b/packages/backend/test/resources/hw.png
new file mode 100644
index 0000000000..afe93faea6
Binary files /dev/null and b/packages/backend/test/resources/hw.png differ
diff --git a/packages/backend/test/unit/activitypub.ts b/packages/backend/test/unit/activitypub.ts
index 9df947982b..ee1afc51ca 100644
--- a/packages/backend/test/unit/activitypub.ts
+++ b/packages/backend/test/unit/activitypub.ts
@@ -6,9 +6,13 @@
 process.env.NODE_ENV = 'test';
 
 import * as assert from 'assert';
+import * as fs from 'node:fs';
 import { Test } from '@nestjs/testing';
 import { jest } from '@jest/globals';
 
+import { MockResolver } from '../misc/mock-resolver.js';
+import type { IActor, IApDocument, ICollection, IObject, IPost } from '@/core/activitypub/type.js';
+import type { MiRemoteUser } from '@/models/User.js';
 import { ApImageService } from '@/core/activitypub/models/ApImageService.js';
 import { ApNoteService } from '@/core/activitypub/models/ApNoteService.js';
 import { ApPersonService } from '@/core/activitypub/models/ApPersonService.js';
@@ -19,14 +23,11 @@ import { GlobalModule } from '@/GlobalModule.js';
 import { CoreModule } from '@/core/CoreModule.js';
 import { FederatedInstanceService } from '@/core/FederatedInstanceService.js';
 import { LoggerService } from '@/core/LoggerService.js';
-import type { IActor, IApDocument, ICollection, IObject, IPost } from '@/core/activitypub/type.js';
 import { MiMeta, MiNote, UserProfilesRepository } from '@/models/_.js';
 import { DI } from '@/di-symbols.js';
 import { secureRndstr } from '@/misc/secure-rndstr.js';
 import { DownloadService } from '@/core/DownloadService.js';
-import type { MiRemoteUser } from '@/models/User.js';
 import { genAidx } from '@/misc/id/aidx.js';
-import { MockResolver } from '../misc/mock-resolver.js';
 
 const host = 'https://host1.test';
 
@@ -120,7 +121,13 @@ describe('ActivityPub', () => {
 			imports: [GlobalModule, CoreModule],
 		})
 			.overrideProvider(DownloadService).useValue({
-				async downloadUrl(): Promise<{ filename: string }> {
+				async downloadUrl(url, path): Promise<{ filename: string }> {
+					if (url.endsWith('.png')) {
+						fs.copyFileSync(
+							`${__dirname}/../resources/hw.png`,
+							path,
+						);
+					}
 					return {
 						filename: 'dummy.tmp',
 					};
@@ -440,7 +447,7 @@ describe('ActivityPub', () => {
 		});
 	});
 
-	describe('JSON-LD', () =>{
+	describe('JSON-LD', () => {
 		test('Compaction', async () => {
 			const jsonLd = jsonLdService.use();