For now you have to dig your way out it is an adventure :). But it seems to be a race condition or related to timing, I haven’t seen this issue locally but I do see it now, logged a bug to investigate later https://github.com/satoshinm/WebSandboxMC/issues/50.
Also, I can’t seem to turn my view. Browser is Vivaldi.
I have not tested much with lesser known browsers, but curiously, testing now with the Brave browser I also see it doesn’t support pointer lock either. And both these browsers are based on Chrome’s Blink layout engine, yet Chrome itself supports Pointer Lock just fine. I’ll see what I can do to better support these niche browsers but my main targets for best support are Chrome, Firefox, and Safari.