Panic on web when using google input tools extension

[WenSimEHRP]

Describe the bug

Typing in textedit widget while having the google input tools enabled in wasm triggers a panic in wasm.

To Reproduce
Steps to reproduce the behavior:

1. Use Chromium and install the Google Input Tools extension
2. Go to https://egui.rs/
3. Enable a Chinese input method (I used Shuangpin (Microsoft), but I think this applies to any CJK input methods)
4. Try entering something with the input tool enabled. The app would crash

Expected behavior

App should not crash

Screenshots

Desktop (please complete the following information):

• OS: Debian 6.12.73-1 (2026-02-17) x86_64 GNU/Linux
• Browser: Version 145.0.7632.159 (Official Build) built on Debian GNU/Linux 13 (trixie) (64-bit)
• On X11

Additional context

the code is defined at https://github.com/wasm-bindgen/wasm-bindgen/blob/6b6aa1ca4732bfd8f2910745e32ba959c094c2ad/crates/cli-support/src/js/mod.rs#L1849

related issues: wasm-bindgen/wasm-bindgen#2746

Console output:

egui_demo_app.js:3184 using deprecated parameters for the initialization function; pass a single object instead
__wbg_init @ egui_demo_app.js:3184
(anonymous) @ (index):129
chext_driver.js:539 Initialized driver at: Mon Mar 09 2026 12:54:19 GMT-0700 (Pacific Daylight Time)
chext_loader.js:73 Initialized chextloader at: 1773086059185
egui_demo_app.js:1393 [eframe::web::web_runner] eframe/src/web/web_runner.rs:93: event handlers installed.
egui_demo_app.js:116 Uncaught TypeError: Cannot read properties of undefined (reading 'length')
    at passStringToWasm0 (egui_demo_app.js:116:23)
    at imports.wbg.__wbg_key_7b5c6cb539be8e13 (egui_demo_app.js:1576:26)
    at 029d0efe:0x7468e3
    at 029d0efe:0x4877b5
    at 029d0efe:0x6d79d8
    at 029d0efe:0x757c5b
    at 029d0efe:0x75eaaa
    at __wbg_adapter_36 (egui_demo_app.js:250:14)
    at HTMLInputElement.real (egui_demo_app.js:170:24)
passStringToWasm0 @ egui_demo_app.js:116
imports.wbg.__wbg_key_7b5c6cb539be8e13 @ egui_demo_app.js:1576
$func6786 @ 029d0efe:0x7468e3
$func2219 @ 029d0efe:0x4877b5
$func4953 @ 029d0efe:0x6d79d8
$func7412 @ 029d0efe:0x757c5b
$closure1243_externref_shim @ 029d0efe:0x75eaaa
__wbg_adapter_36 @ egui_demo_app.js:250
real @ egui_demo_app.js:170

[WenSimEHRP]

A simple fix is to replace the panicking line with

let len = arg.length ?? 0;
// or this
let len;
try {
    len = arg.length;
} catch (error) {
    len = 0;
}