When building an app, I get the error:
emscripten.py", line 227, in compiler_glue
assert not (metadata['simd'] and shared.Settings.WASM), 'SIMD is used, but not supported in WASM mode yet'
AssertionError: SIMD is used, but not supported in WASM mode yet
I have tracked it down to the commit:
02280535be Update bundled Freetype to 2.9.1