firefox gets slower and slower over time.
I have been using firefox for some time, Like it better than Safari generally, but I've noticed (and it has gotten worse with 3.6.x) that if you leave FF running for extended periods of time it gets slower and slower, does not seem to matter if add-ons are installed or not, and it gets REALLY bad after going in and out of flash based apps/games a couple times. It is not just a mac problem as this behaviour also happens on windows xp or newer, but windows OS needs to be rebooted daily anyways so most people won't notice.
Alle svar (1)
Proceed with Troubleshoot and diagnose Firefox problems first of all.
You could also try running Firefox in Diagnose Firefox issues using Troubleshoot Mode. If it functions properly in that configuration, then one of your add-ons is the culprit.