When any thai characters are being used in a QML Text object as text, the application is crashing and the following error is printed into the Javascript console : 
"
VM221:1 Uncaught RuntimeError: Aborted(To use dlopen, you need to use Emscripten's linking support, see https://github.com/emscripten-core/emscripten/wiki/Linking). Build with -s ASSERTIONS=1 for more info.
at ye (eval at completeLoadEmscriptenModule (qtloader.js:1:5259), <anonymous>:1:5701)
at ua (eval at completeLoadEmscriptenModule (qtloader.js:1:5259), <anonymous>:1:116703)
"

To reproduce the issue, just simply build and run the attached project for WebAssembly (I used Qt 6.4.1) : 
WebAssemblyThaiCharactersCrash.zip