I had similar things with shader demos. One thing is for sure, faulty JS can mess your browser up heavily. I spent hours debugging a bug that just vanished after I restarted the browser, for instance. Other than that, try to get the latest updates for the involved software: the os, the GPU and the browser. Also, try other browsers. I use mozilla based (I think) BRAVE and also, surprisingly: Edge, because hard to believe but Edgne performs best with WebGL. Tho, they say Edge is now based on Chrome... which would be Google - not a fan of monopolies.