My helloworld app does not work with flutter-pi

[volkrass]

Hi, might be you can give me an advice.

I create a simple app with following command my host machine:
flutter create helloworld
cd helloworld
flutter build bundle

Then I copied my flutter_asset folder to my RaspPI
When I try to start the app with flutter-pi I get following dump:

asset_bundle_path: ./helloworld
initializing display...
Initializing bcm_host...
Getting the EGL display...
Initializing EGL...
Choosing an EGL config...
Creating the EGL context...
Querying the display size...
Opening the dispmanx display...
Setting up the dispmanx display...
Creating the EGL window surface...
Initializing Input devices...
Initializing Application...
[ERROR:flutter/shell/platform/embedder/embedder_surface_gl.cc(95)] Could not create a resource context for async texture uploads. Expect degraded performance. Set a valid make_resource_current callback on FlutterOpenGLRendererConfig.
calling proc_resolver with glGetString
...
calling proc_resolver with glGetShaderPrecisionFormat
[ERROR:flutter/shell/platform/embedder/embedder_surface_gl.cc(95)] Could not create a resource context for async texture uploads. Expect degraded performance. Set a valid make_resource_current callback on FlutterOpenGLRendererConfig.
Running IO thread...
Running message loop...
flutter: Observatory listening on http://127.0.0.1:45969/Lsd268iTVj8=/
flutter: ══╡ EXCEPTION CAUGHT BY WIDGETS LIBRARY ╞═══════════════════════════════════════════════════════════
flutter: The following assertion was thrown building MyApp(dirty):
flutter: Unknown platform.
flutter: linux was not recognized as a target platform. Consider updating the list of TargetPlatforms to
flutter: include this platform.
flutter:
flutter: When the exception was thrown, this was the stack:
flutter: #0 defaultTargetPlatform (package:flutter/src/foundation/_platform_io.dart:27:5)
...

Desktop support ist enabled.

export ENABLE_FLUTTER_DESKTOP=true

I'm pretty sure I missed a step, because the example app from flutter-desktop-embedding works without any problem

[volkrass]

Have to patch my main.dart file like explained here:
https://github.com/flutter/flutter/wiki/Desktop-shells#target-platform-override