Four interfaces (WebGLQuery, WebGLSampler, WebGLSync, and WebGLTransformFeedback) that are available only in WebGL 2.0 have EnabledBySetting=WebGLEnabled instead of EnabledBySetting=WebGL2Enabled. I suggest adjusting that. Alternatively, maybe it's time to remove that setting altogether? Virtually all WebGL 2.0 only interfaces (except three) have Conditional=WEBGL instead of Conditional=WEBGL2. No idea what's implied there.
*** This bug has been marked as a duplicate of bug 248667 ***