Since I installed Firefox 9.0.1 I used to blame my computer for its low performance.
Actually Firefox is the one that is too slow. If you have the same problem, if websites load at a slow speed, if tabs navigation is a pain and they change too slow, and if typing an email is a real slowly action since the new Firefox 9, then read the solution that will solve this problem.
While some would choose to reinstall Firefox 3.0.6 which is not at all slow, the others will solve the problem lime this:
In order to render faster, Firefox has the option for hardware acceleration. What to say.. this option in Firefox actually slows down the performance.
Go to Tools -> Options -> Advanced -> General and uncheck the option for hardware acceleration.
You will have the speed you expect from Firefox, you will see that it won’t be slow at all.