Firefox v15 and up cause my computer (MAC OSX 10.8.2) to freeze for about 30 seconds every 15-30 seconds and forces me to turn it off with the power button. It only causes this after I have opened Firefox, my computer runs fine before opening Firefox. I have uninstalled Firefox and cleared my personal settings. I have installed future updates (16 and 17) and have run into the same issue. I cannot pull any information on RAM or CPU usage because when it happens it makes my computer unusable. Unfortunately I need to use FF for work and can't. I have tried the different responses on the forums to reduce the amount of RAM and CPU usage with no change in performance.