Disable MultiThreading on WASM for now

[Arlodotexe]

MultiThreading won't make a big difference in performance since we aren't doing a lot of thread-heavy work in our sample app. This feature has been disabled for now until it's needed again or until the SharedArrayBuffer workaround is no longer needed.

[michael-hawker]

@Arlodotexe is there an issue tracking that for Uno or something, assume this is a .NET 8 related thing maybe?

[Arlodotexe]

@Arlodotexe is there an issue tracking that for Uno or something, assume this is a .NET 8 related thing maybe?

No, we just don't need it for now. We enabled all wasm optimizations when upgrading to .NET 7, this was one, but it's not high-impact enough to keep turned on.

Browsers currently require certain server-side CORS flags to be enabled for SharedArrayBuffer to be usable, a remnant of the Specter/Meltdown CPU vulnerabilities from a few years ago. Our workaround requires refreshing after the ServiceWorker is registered (which it tries), but it's busted and it's not clear why.

MultiThreading won't make a big difference in performance since we aren't doing a lot of thread-heavy work in our sample app. This feature has been disabled for now until it's needed again or until the SharedArrayBuffer workaround is no longer needed.