There are pauses, even worse than in Chrome. Use MemChaser add-on to see GC activity in FF. In Firefox Nightly on the particle demo I have non-incremental 0.6-0.7s pauses every ~10s (not to mention stutter from incremental GC in between the big pauses). In Chrome on the same sample I just don't have any pauses longer than 0.1-0.2s (every ~2s).
Firefox has been working on an incremental GC
I believe that they have been using an incremental GC since version 16.
Correct. In profiles I typically observe incremental GC running in 1-5ms increments, which makes it easier for it to fit in between frames without causing visible stutter.
Firefox on a tf700 dies horribly at around 3 fps.
I wonder how webgl will perform on the predominant browser platform - mobile.