This would only occur when WebInspector is open on the page, similar to the backtrace of the creation of the canvas context.
I created this bug to discuss the usefulness/validity of this addition. I am still not convinced that it would be useful, but I also have never programmed with WebGL. Does anyone else have any thoughts?
Yeah when I saw this bug I didn't think it would be useful. I'd guess extensions are enabled in one place, and probably would be easy to search for.
Tangentially, what might be useful would be toggling extensions on / off. I'm not sure to what degree that is possible.