OS X Firefox Users – Don’t Hold That Button!
December 1, 2005
There is an article causing a bit of a ripple this morning claiming a “major bug” in Firefox under OS X.
There is a major bug in Firefox where if you hold down the mouse button to select text, or scroll, or anything inside the browser window, the Firefox CPU usage shoots up to nearly 100% and hogs your entire system until you let go. I just tested it using top and can verify that the CPU usage jumps to between 75-95% depending on the other applications in use at the time. For Powerbook or iBook users this is a major issue, considering your fans will probably turn on and you’ll battery will drain much quicker.
This is real, but it’s apparently a bug in Carbon (one of several methods of writing applications for OS X) in general, and not just Firefox.
It’s also been there from the beginning, and appears to be slightly better in 1.5 than it was in 1.0x — I’ve noticed several times running Firefox over the past few months that holding down the mouse button and selecting text would occasionally cause the machine to slow up for a few seconds.
The good news is that the problem goes away when you let go of the button — which makes this more of just an annoyance than anything.
Which is not to say it shouldn’t be fixed (apparently there are some coding fixups that would allow Firefox to improve this behavior somewhat, even while remaining a Carbon app), but more to say that if you are a Mac user, you shouldn’t let reports of this “major bug” keep you from enjoying this fine new release of Firefox.