DevicePreview.screenshot throws Error: Unexpected null value

[JonasJW]

I'm getting this weird error when calling DevicePreview.screenshot(context). This only happens on one specific page only on the web platform. Other pages work fine and it works on iOS.

I couldn't find any more info while debugging that might explain this error, I only have the following exception. I assume this is not much help to identify the issue but I still want to see if someone has an idea.

Error: Unexpected null value.
../dart-sdk/lib/_internal/js_dev_runtime/private/ddc_runtime/errors.dart 266:49      throw_
../dart-sdk/lib/_internal/js_dev_runtime/private/ddc_runtime/operations.dart 528:63  nullCheck
../lib/_engine/engine/canvaskit/layer.dart 584:34                                    preroll
../lib/_engine/engine/canvaskit/layer.dart 125:12                                    prerollChildren
../lib/_engine/engine/canvaskit/layer.dart 357:9                                     preroll
../lib/_engine/engine/canvaskit/layer.dart 125:12                                    prerollChildren
../lib/_engine/engine/canvaskit/layer.dart 197:38                                    preroll
../lib/_engine/engine/canvaskit/layer.dart 125:12                                    prerollChildren
../lib/_engine/engine/canvaskit/layer.dart 357:9                                     preroll
../lib/_engine/engine/canvaskit/layer.dart 125:12                                    prerollChildren
../lib/_engine/engine/canvaskit/layer.dart 237:38                                    preroll
../lib/_engine/engine/canvaskit/layer.dart 125:12                                    prerollChildren
../lib/_engine/engine/canvaskit/layer.dart 357:9                                     preroll
../lib/_engine/engine/canvaskit/layer.dart 125:12                                    prerollChildren
../lib/_engine/engine/canvaskit/layer.dart 357:9                                     preroll
../lib/_engine/engine/canvaskit/layer.dart 125:12                                    prerollChildren
../lib/_engine/engine/canvaskit/layer.dart 357:9                                     preroll
../lib/_engine/engine/canvaskit/layer.dart 125:12                                    prerollChildren
../lib/_engine/engine/canvaskit/layer.dart 237:38                                    preroll
../lib/_engine/engine/canvaskit/layer.dart 125:12                                    prerollChildren
../lib/_engine/engine/canvaskit/layer.dart 357:9                                     preroll
../lib/_engine/engine/canvaskit/layer.dart 125:12                                    prerollChildren
../lib/_engine/engine/canvaskit/layer.dart 357:9                                     preroll
../lib/_engine/engine/canvaskit/layer.dart 125:12                                    prerollChildren
../lib/_engine/engine/canvaskit/layer.dart 197:38                                    preroll
../lib/_engine/engine/canvaskit/layer.dart 125:12                                    prerollChildren
../lib/_engine/engine/canvaskit/layer.dart 357:9                                     preroll
../lib/_engine/engine/canvaskit/layer.dart 125:12                                    prerollChildren
../lib/_engine/engine/canvaskit/layer.dart 357:9                                     preroll
../packages/bardogs_flutter/my_app.dart 213:22                                       <fn>
../packages/flutter/src/material/ink_well.dart 1072:21                               handleTap
../packages/flutter/src/gestures/recognizer.dart 253:24                              invokeCallback
../packages/flutter/src/gestures/tap.dart 627:11                                     handleTapUp
../packages/flutter/src/gestures/tap.dart 306:5                                      [_checkUp]
../packages/flutter/src/gestures/tap.dart 239:7                                      handlePrimaryPointer
../packages/flutter/src/gestures/recognizer.dart 615:9                               handleEvent
../packages/flutter/src/gestures/pointer_router.dart 98:12                           [_dispatch]
../packages/flutter/src/gestures/pointer_router.dart 143:9                           <fn>
../dart-sdk/lib/_internal/js_dev_runtime/private/linked_hash_map.dart 21:13          forEach
../packages/flutter/src/gestures/pointer_router.dart 141:17                          [_dispatchEventToRoutes]
../packages/flutter/src/gestures/pointer_router.dart 127:7                           route
../packages/flutter/src/gestures/binding.dart 460:19                                 handleEvent
../packages/flutter/src/gestures/binding.dart 440:14                                 dispatchEvent
../packages/flutter/src/rendering/binding.dart 337:11                                dispatchEvent
../packages/flutter/src/gestures/binding.dart 395:7                                  [_handlePointerEventImmediately]
../packages/flutter/src/gestures/binding.dart 357:5                                  handlePointerEvent
../packages/flutter/src/gestures/binding.dart 314:7                                  [_flushPointerEventQueue]
../packages/flutter/src/gestures/binding.dart 295:7                                  [_handlePointerDataPacket]
../lib/_engine/engine/platform_dispatcher.dart 1183:13                               invoke1
../lib/_engine/engine/platform_dispatcher.dart 244:5                                 invokeOnPointerDataPacket
../lib/_engine/engine/pointer_binding.dart 147:39                                    [_onPointerData]
../lib/_engine/engine/pointer_binding.dart 653:20                                    <fn>
../lib/_engine/engine/pointer_binding.dart 594:14                                    <fn>
../lib/_engine/engine/pointer_binding.dart 288:16                                    loggedHandler
../lib/_engine/engine/pointer_binding.dart 179:80                                    <fn>
../dart-sdk/lib/_internal/js_dev_runtime/private/ddc_runtime/operations.dart 334:14  _checkAndCall
../dart-sdk/lib/_internal/js_dev_runtime/private/ddc_runtime/operations.dart 339:39  dcall

[xalikoutis]

i believe it is impeller issue. Disable impeller and it should work