I tried on my pinephone, made it all the way to actually rendering a frame of 3D gameplay then either didn't have working controls or froze. And I expected it to crash the browser (firefox). So well done!
Thanks! In our testing, Firefox is about 40% slower than Chromium-based browsers or Safari. Would be interesting to know what the performance was like with Chromium on that device! https://download-chromium.appspot.com/