How does the text input work there? Does it support IME? Were you able to switch to non-latin keyboards?

I think it is handled by the OS (backend renderer)

But, I have only used it with Romanian and English.

Try here: https://slintpad.com/. (just replace the Text with TextInput) and see if it works.

	▲	ogoffart 4 hours ago \| parent [-]
		slintpad.com uses the wasm port to run on a browser and is not the same as when using Slint to build a "native" app, especially on mobile. Slint does support decent text input and IME. Including text selection with the native handle. As a demo for android you can try the demo from https://material.slint.dev/ ("Download APK")