Phab doesn't work with Firefox
I recently got fed up with Chrome's attempts to notify me about things which I don't wish to be notified, and decided to go (back) to Firefox. But, now I discover that Firefox doesn't work completely with Phab! Specifically, on a differential page, I can't click on the little down-arrow to the right of a comment (the one that pulls up the menu containing the "Quote" option), useful if I want to reply. Clicking there has no effect, and my cursor becomes the shape it usually does when I'm about to enter text, not an arrow.
I'm using Firefox version 34.0.5, which claims it is up-to-date.