The beautiful wonder that is Javascript. All the majesty of a killer whale piloting a single-engine supercruiser via a blue-tooth repeater connected 500m gallon tank in the Sahara. Think about how flexible such a system can be!
Oh, Definitely! It couldn't be the layers of parsers, spaghetti Javascript libraries, web protocols, the DOM, WebGL itself which is a part of Javascript, or a million other crufty web things, it has to be the microsecond latency introduced by hardware-level API abstraction...
User-level libraries can't lock up your OS unless they can trigger kernel / driver bugs or make your hardware malfunction. In this case, graphics drivers are the most likely cause.