Install Qt 6.5.0 beta2 WebAssembly binaries (single or multithread, reproduces on both), include QtQuick3D to installation. Finish installation and see installed content, following files do not exists anymore in beta2, but were present in beta1 (and first beta2 snapshot):
Are those removed intentionally? (I tried to look for a commit that would remove those, but I couldn't spot any...)
Edit, affects also iOS.
Edit2, affects also WoA.