diff --git a/test/batch_test.dart b/test/batch_test.dart
index 68732f4..752a802 100644
--- a/test/batch_test.dart
+++ b/test/batch_test.dart
@@ -1,3 +1,4 @@
+import 'dart:async';
 import 'dart:io';
 
 import 'package:flutter/material.dart';
@@ -15,6 +16,7 @@ import 'package:jj_mkvmaker/platform/windows/desktop_storage_service.dart';
 import 'package:jj_mkvmaker/platform/windows/process_media_tool.dart';
 import 'package:jj_mkvmaker/services/ai_services.dart';
 import 'package:jj_mkvmaker/services/downloader.dart';
+import 'package:jj_mkvmaker/services/media_tool.dart';
 import 'package:jj_mkvmaker/services/model_store.dart';
 import 'package:jj_mkvmaker/services/platform_services.dart';
 import 'package:jj_mkvmaker/ui/app_actions.dart';
@@ -36,6 +38,35 @@ class _Recognizer implements SpeechRecognizer {
   }
 }
 
+/// 240: 취소될 때까지 끝나지 않는 FFmpeg (여럿이 동시에 도는 상태를 만든다)
+class _HoldTool implements MediaTool {
+  final runs = <Object?, Completer<void>>{};
+  @override
+  Future<String?> version() async => 'ffmpeg test';
+  @override
+  Future<Set<String>> encoders() async => {'libx264'};
+  @override
+  Future<MediaInfo> probe(String path) async => const MediaInfo(duration: Duration(seconds: 1));
+  @override
+  Future<void> runFfmpeg(List<String> args, {Duration? duration, ProgressCallback? onProgress, Object? tag}) async {
+    final c = runs[tag] = Completer<void>();
+    try {
+      await c.future;
+    } finally {
+      runs.remove(tag);
+    }
+  }
+
+  void _stop(Completer<void>? c) {
+    if (c != null && !c.isCompleted) c.completeError(MediaToolException('사용자가 취소했습니다.'));
+  }
+
+  @override
+  void cancel() => runs.values.toList().forEach(_stop);
+  @override
+  void cancelTagged(Object tag) => _stop(runs[tag]);
+}
+
 class _Translator implements Translator {
   @override
   Future<void> load(String modelDir) async {}
@@ -504,4 +535,50 @@ void main() {
     await tester.pumpWidget(const SizedBox());
     d.dispose();
   });
+
+  testWidgets('240: 여럿이 동시에 돌 때 ■ 는 묻는다 ([그대로 두기] · [모두 취소 (n개)]) · 목록 줄의 ■ 는 그 동영상만', (tester) async {
+    tester.view.physicalSize = const Size(1600, 900);
+    tester.view.devicePixelRatio = 1;
+    addTearDown(tester.view.reset);
+    final tool = _HoldTool();
+    final dir = Directory.systemTemp.createTempSync('jj_batch240_');
+    addTearDown(() => dir.deleteSync(recursive: true));
+    final files = [
+      for (final n in ['a', 'b']) (File(p.join(dir.path, '$n.mp4'))..writeAsBytesSync([0])).path,
+    ];
+    final c = AppController(PlatformServices(mediaTool: tool, storage: DesktopStorageService()));
+    late Future<void> building;
+    await tester.runAsync(() async {
+      await c.init();
+      c.settings.maxParallelJobs = 5;
+      await c.addVideos(files);
+      building = c.buildVideos([...c.videos]);
+      for (var i = 0; i < 200 && tool.runs.length < 2; i++) {
+        await Future<void>.delayed(const Duration(milliseconds: 10));
+      }
+    });
+    final [a, b] = c.videos;
+    expect([a.status, b.status], [JobStatus.running, JobStatus.running]);
+    await tester.pumpWidget(MaterialApp(home: HomePage(c: c)));
+    await tester.pump();
+    // ■ (위 막대): 둘이 돌고 남은 것은 없음 → 묻는다
+    await tester.tap(find.byTooltip('작업 취소').first);
+    await tester.pump(const Duration(milliseconds: 400)); // 도는 동안은 진행 막대가 움직여 pumpAndSettle 이 끝나지 않는다
+    expect(find.text('모두 취소 (2개)'), findsOneWidget);
+    await tester.tap(find.text('그대로 두기'));
+    await tester.pump(const Duration(milliseconds: 400)); // 도는 동안은 진행 막대가 움직여 pumpAndSettle 이 끝나지 않는다
+    expect(tool.runs.length, 2, reason: '[그대로 두기] 는 아무것도 취소하지 않음');
+    // 목록 줄의 ■: 그 동영상만
+    expect(find.byTooltip('이 동영상만 취소'), findsNWidgets(2));
+    await tester.tap(find.byTooltip('이 동영상만 취소').first);
+    await tester.runAsync(() => Future<void>.delayed(const Duration(milliseconds: 100)));
+    await tester.pump();
+    expect([a.status, b.status], [JobStatus.cancelled, JobStatus.running]);
+    // 하나만 남으면 ■ 는 묻지 않고 바로 취소
+    await tester.tap(find.byTooltip('작업 취소').first);
+    await tester.runAsync(() => building);
+    await tester.pump();
+    expect(b.status, JobStatus.cancelled);
+    expect(find.text('모두 취소 (2개)'), findsNothing);
+  });
 }