Better perf on mobile

[steren]

Currently, doesn't run on mobile, probably due to large canvas size.

Try detecting memory / CPU available?

[steren]

Use Compute Pressure API?
https://developer.chrome.com/blog/compute-pressure-origin-trial-2/

[steren]

Tried in 52058a4, but it can only observe cpu

[steren]

Use Timestamp queries? https://gpuweb.github.io/gpuweb/#timestamp