I was trying it in Opera. A chromium based browser that always had WebGL as far as I know. Even the previous version had optional WebGL (so user agent blocking would not made sense either). So unless this code was written 5 years ago, it's useless. And even if it was, it's obviously badly written and useless as well.

> well aware of the mess that is browser detection

It's a mess because people use it for other things than statistics. "Use IE5+" era apparently taught developers absolutely nothing.