refactor: workaround capture issue

flutter/lib/src/event_processor/screenshot_event_processor.dart

@@ -9,7 +9,6 @@ import '../screenshot/recorder.dart';
 import '../screenshot/recorder_config.dart';
 import 'package:flutter/widgets.dart' as widget;
 
-import '../screenshot/stabilizer.dart';
 import '../utils/debouncer.dart';
 
 class ScreenshotEventProcessor implements EventProcessor {
@@ -126,37 +125,6 @@ class ScreenshotEventProcessor implements EventProcessor {
   }
 
   @internal
-  Future<Uint8List?> createScreenshot() async {
-    if (_options.experimental.privacyForScreenshots == null) {
-      return _recorder.capture((screenshot) =>
-          screenshot.pngData.then((v) => v.buffer.asUint8List()));
-    } else {
-      // If masking is enabled, we need to use [ScreenshotStabilizer].
-      final completer = Completer<Uint8List?>();
-      final stabilizer = ScreenshotStabilizer(
-        _recorder, _options,
-        (screenshot) async {
-          final pngData = await screenshot.pngData;
-          completer.complete(pngData.buffer.asUint8List());
-        },
-        // This limits the amount of time to take a stable masked screenshot.
-        maxTries: 5,
-        // We need to force the frame the frame or this could hang indefinitely.
-        frameSchedulingMode: FrameSchedulingMode.forced,
-      );
-      try {
-        unawaited(
-            stabilizer.capture(Duration.zero).onError(completer.completeError));
-        // DO NOT return completer.future directly - we need to dispose first.
-        return await completer.future.timeout(const Duration(seconds: 1),
-            onTimeout: () {
-          _options.logger(
-              SentryLevel.warning, 'Timed out taking a stable screenshot.');
-          return null;
-        });
-      } finally {
-        stabilizer.dispose();
-      }
-    }
-  }
+  Future<Uint8List?> createScreenshot() => _recorder.capture(
+      (screenshot) => screenshot.pngData.then((v) => v.buffer.asUint8List()));
 }

flutter/lib/src/native/cocoa/cocoa_replay_recorder.dart

@@ -6,24 +6,24 @@ import '../../../sentry_flutter.dart';
 import '../../replay/replay_recorder.dart';
 import '../../screenshot/recorder.dart';
 import '../../screenshot/recorder_config.dart';
-import '../../screenshot/stabilizer.dart';
 import '../native_memory.dart';
 
 @internal
 class CocoaReplayRecorder {
   final SentryFlutterOptions _options;
   final ScreenshotRecorder _recorder;
-  late final ScreenshotStabilizer<void> _stabilizer;
-  var _completer = Completer<Map<String, int>?>();
 
   CocoaReplayRecorder(this._options)
       : _recorder = ReplayScreenshotRecorder(
-            ScreenshotRecorderConfig(
-              pixelRatio:
-                  _options.experimental.replay.quality.resolutionScalingFactor,
-            ),
-            _options) {
-    _stabilizer = ScreenshotStabilizer(_recorder, _options, (screenshot) async {
+          ScreenshotRecorderConfig(
+            pixelRatio:
+                _options.experimental.replay.quality.resolutionScalingFactor,
+          ),
+          _options,
+        );
+
+  Future<Map<String, int>?> captureScreenshot() async {
+    return _recorder.capture((screenshot) async {
       final data = await screenshot.rawRgbaData;
       _options.logger(
           SentryLevel.debug,
@@ -35,15 +35,7 @@ class CocoaReplayRecorder {
       final json = data.toNativeMemory().toJson();
       json['width'] = screenshot.width;
       json['height'] = screenshot.height;
-      _completer.complete(json);
-    });
-  }
-
-  Future<Map<String, int>?> captureScreenshot() async {
-    _completer = Completer();
-    _stabilizer.ensureFrameAndAddCallback((msSinceEpoch) {
-      _stabilizer.capture(msSinceEpoch).onError(_completer.completeError);
+      return json;
     });
-    return _completer.future;
   }
 }

flutter/lib/src/replay/scheduled_recorder.dart

@@ -1,9 +1,9 @@
 import 'dart:async';
 
+import 'package:flutter/scheduler.dart';
 import 'package:meta/meta.dart';
 
 import '../../sentry_flutter.dart';
-import '../screenshot/stabilizer.dart';
 import '../screenshot/screenshot.dart';
 import 'replay_recorder.dart';
 import 'scheduled_recorder_config.dart';
@@ -19,7 +19,6 @@ class ScheduledScreenshotRecorder extends ReplayScreenshotRecorder {
   late final ScheduledScreenshotRecorderCallback _callback;
   var _status = _Status.running;
   late final Duration _frameDuration;
-  late final ScreenshotStabilizer<void> _stabilizer;
   // late final _idleFrameFiller = _IdleFrameFiller(_frameDuration, _onScreenshot);
 
   @override
@@ -35,15 +34,23 @@ class ScheduledScreenshotRecorder extends ReplayScreenshotRecorder {
     _frameDuration = Duration(milliseconds: 1000 ~/ config.frameRate);
     assert(_frameDuration.inMicroseconds > 0);
 
-    _stabilizer = ScreenshotStabilizer(this, options, _onImageCaptured);
-    _scheduler = Scheduler(_frameDuration, _stabilizer.capture,
-        _stabilizer.ensureFrameAndAddCallback);
+    _scheduler = Scheduler(
+      _frameDuration,
+      (_) => capture(_onImageCaptured),
+      _addPostFrameCallback,
+    );
 
     if (callback != null) {
       _callback = callback;
     }
   }
 
+  void _addPostFrameCallback(FrameCallback callback) {
+    options.bindingUtils.instance!
+      ..ensureVisualUpdate()
+      ..addPostFrameCallback(callback);
+  }
+
   set callback(ScheduledScreenshotRecorderCallback callback) {
     _callback = callback;
   }
@@ -63,12 +70,10 @@ class ScheduledScreenshotRecorder extends ReplayScreenshotRecorder {
   }
 
   Future<void> _stopScheduler() {
-    _stabilizer.stopped = true;
     return _scheduler.stop();
   }
 
   void _startScheduler() {
-    _stabilizer.stopped = false;
     _scheduler.start();
 
     // We need to schedule a frame because if this happens in-between user
@@ -82,7 +87,6 @@ class ScheduledScreenshotRecorder extends ReplayScreenshotRecorder {
     options.logger(SentryLevel.debug, "$logName: stopping capture.");
     _status = _Status.stopped;
     await _stopScheduler();
-    _stabilizer.dispose();
     // await Future.wait([_stopScheduler(), _idleFrameFiller.stop()]);
     options.logger(SentryLevel.debug, "$logName: capture stopped.");
   }

flutter/lib/src/screenshot/recorder.dart

@@ -190,6 +190,18 @@ class _Capture<R> {
       final recorder = PictureRecorder();
       final canvas = Canvas(recorder);
       final image = await futureImage;
+
+      // Note: there's a weird bug when we write image to canvas directly.
+      // If the UI is updating quickly in some apps, the image could get
+      // out-of-sync with the UI and/or it can get completely mangled.
+      // This can be reproduced, for example, by switching between Spotube's
+      // Search vs Library (2nd and 3rd bottom bar buttons).
+      // Weirdly, dumping the image data seems to prevent this issue...
+      {
+        // we do so in a block so it can be GC'ed early.
+        final _ = await image.toByteData();
+      }
+
       try {
         canvas.drawImage(image, Offset.zero, Paint());
       } finally {

flutter/test/event_processor/screenshot_event_processor_test.dart

@@ -68,27 +68,6 @@ void main() {
     await _addScreenshotAttachment(tester, null, added: true, isWeb: false);
   });
 
-  testWidgets('does not block if the screenshot fails to stabilize',
-      (tester) async {
-    fixture.options.automatedTestMode = false;
-    fixture.options.experimental.privacy.maskAllText = true;
-    // Run with real async https://stackoverflow.com/a/54021863
-    await tester.runAsync(() async {
-      final sut = fixture.getSut(null, false);
-
-      await tester.pumpWidget(SentryScreenshotWidget(
-          child: Text('Catching Pokémon is a snap!',
-              textDirection: TextDirection.ltr)));
-
-      final throwable = Exception();
-      event = SentryEvent(throwable: throwable);
-      hint = Hint();
-      await sut.apply(event, hint);
-
-      expect(hint.screenshot, isNull);
-    });
-  });
-
   testWidgets('adds screenshot attachment with canvasKit renderer',
       (tester) async {
     await _addScreenshotAttachment(tester, FlutterRenderer.canvasKit,