Flutter >= 3.38 keeps its EGL contexts on the raster thread, so
media_kit's video output found none on the platform thread and fell
back to software rendering (no shaders, ~5 fps) on X11. The patched
output opens Flutter's EGL display itself, steps GDK's GLX context aside
on X11 and releases its own context. Patch from a friend's agent, kept
in third_party/media_kit_video/starsync/. Wayland/NVIDIA still renders
on the GPU (checked); the X11 path was verified on the friend's machine.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>