The frameSwapped() signal produces a terrible choppy animation on desktop, but a nice smooth animation on Android and WASM.

I attached a source code (see the simple-keyframe-animation-opengles2-qt6-cpp.zip file) of my simple example with keyframe animation on QOpenGLWindow.

Try to run the WASM example: https://6606cb229a3fbbbdbb1d4ab5--resonant-brioche-d1b569.netlify.app/

Or Android example: see the attached simple-keyframe-animation-opengles2-qt6-cpp-android-apk.zip file)

And compare it with desktop example: see the attached simple-keyframe-animation-opengles2-qt6-cpp-win10x64-exe.zip file

You will see that the frameSwapped() signal produces a terrible choppy animation on desktop, but a nice smooth animation on Android and WASM.