[jasin]

Me too, and as it happens, I'm running on retina with "more space" enabled. Firefox is unusably slow, to the point where I'm probably abandoning it after a few weeks of really trying to get into it. Which is a shame, because I love the idea of multi-account containers and other privacy features.

[retSava]

So if you disable the "more space" configuration, does it work better? If this is the primo hypothesis, it sounds easy enough to check.

[jasin]

It certainly does seem to work better with default resolution.