Bug with WS global patching causing netplay black screen
## Bug description
Currently, netplay URLs do not load on desktop web and mobile web.

## Reproduce
On any computer browser (e.g. chrome), visit a wasm4 game (e.g. https://wasm4.org/play/kittygame) and press `enter->copy netplay URL`. Now open another tab and paste. Observe a black screen. Open developer console and see the error:

```
Uncaught (in promise) TypeError: set WebAssembly.Global.value): Can't set the value of an immutable global.
    at Ct.write (wasm4.js:50:9105)
    at RTCDataChannel.<anonymous> (wasm4.js:50:20165)
```

## Fix exploration

Now observe that if you use devtool source overrides (https://stackoverflow.com/a/61377922), comment out the problematic line (wasm4.js line 50), save, and reload, netplay functions as normal.

This appears to be caused by #715 with [this specific change](https://github.com/aduros/wasm4/pull/715/files#diff-5350282c31672fdefd1b39369d867d93f50436c107f1779ed80f86dec486f6acR41). @JerwuQu any ideas for a fix? I could look myself but I don't want to jump in and break global patching, as I don't know how that part of the codebase works just yet.