Firefox, like human celebrities, has taken a familiar road, going from the much-loved #1 web browser that everyone liked to a fat lazy shadow of its former self that doesn't do a darn thing right anymore, but doesn't really want to admit it.
I switched 100% to Chrome as of yesterday and have had zero problems so far. I'd personally recommend doing the same if at all possible - Firefox shows no signs of improving.
Is Opera an Apple product? I was unaware...