QML Text controls don't accept pasting Chinese text

Tested on Windows 11 Pro 23H2, Emscripten 3.1.52, Version 129.0.6668.70 (Official Build) (64-bit)

Note: Qt Online Documentation were not released for Qt 6.8, and testing is done by building Qt examples in Qt Creator

Test steps:
1. Built and run QML Gallery example (gallery_controls2) for single-threaded, multi-threaded WebAssembly and desktop
2. Tested each control in the gallery example and compared with behavior against desktop application

Expected results:
1. The QML Gallery example controls behave the same way on WebAssembly as on desktop.

Observed results:
2. Controls behave the same way on single-threaded WebAssembly, multi-threaded WebAssembly, and desktop, with the exception of TextArea and TextField QML controls. The difference with these two controls is that pasting Chinese text into them is not supported with the following input string (這是一份非常簡單的說明書…), and instead of displaying the chinese characters, the text fields show replacement squares.