I realise this topic is 4 months old,but..
Just looked at the 3D mode and also got "RuntimeError: The browser supports WebGL, but initialization failed."
However, I was able to get it working by making sure 'Use hardware acceleration when available' is enabled in Chrome settings, then adding this flag --ignore-gpu-blacklist to the chrome shortcut (right click shortcut>Properties) then at the end of the Target box add a space, followed by the flag --ignore-gpu-blacklist
eg "C:\Program Files (x86)\Google\Chrome\Application" --ignore-gpu-blacklist