Yeah I'm having a hard time with my group too. We're leaving it mostly off these days. Shame really. I think this is likely a combination of graphics drivers and browser behavior. In Chrome you can fiddle around with it. The lighting is canvas, the 3D dice are WebGL. So open chrome://gpu/ and look at Canvas. If it says Canvas is "Hardware accelerated", you can go to chrome://flags/ and Enable the "Disable accelerated 2D canvas" feature (I know, positive on a negative, or something, my poor brain), relaunch Chrome, and after that chrome://gpu/ should show that you're using software rendering. Which might fix the crashes, but now of course everything is going to be dog slow. The DM can help with the slow bit a little bit by enabling "only update on drop" and maybe disabling "force line of sight", both of which he'd do on an individual map. You can also see whether updating your graphics drivers does you any good. If you like, I'm willing to test this with you on a lighting-enabled map, only because it'd teach me something about the troubles my own players are facing. I'd love to use dynamic lighting in my campaign, and if I can get closer to figuring out how to do that with a bunch of different hardware out there, I'm all for it.
