New answers tagged firefox
Try logging out and back in. I know that sounds like a "grasping at straws"-type solution, but this is the sort of doesn't-make-sense kind of problem that I've seen fixed by logging out (or maybe even restarting).
As of now (Dec 1 2014), although the option is not present in right-click menu, three-finger dictionary lookup works perfectly fine in my Firefox (Developer Edition 35)
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