Is there a reason you are using the Accessibility Services at all ?

As this is the solution for excessive ram/cpu usage :

please : go to the Firefox 3 Bar Menu --> Options --> Privacy & Security panel and under Permissions check (put a tick in the box) the setting to Prevent Accessibility Services from accessing your browser.

Monitor in Task Manager. Should stay below 2 gigs. If excessive then do below and monitor and change if need to...Test and go up again , go back down, it will eventually get a zone you and it can live with.

Go to the 3 Bar Menu then Options --> General --> Performance and untick everything. change the recommended size lower then see how it runs. Note: 1 = No Multiprocessor = slow again. Try 2 Restart Firefox after making these changes please.

Please let us know if this solved your issue or if need further assistance.

thanks for the reply.

Prevent Accessibility Services from accessing your browser, box is still checked. i dont think i have the need for this

Monitor in Task Manager. Should stay below 2 gigs. mine initially said > 4 gbs, now after setting recommended size to 2 it is saying 765 mb. so far it is looking good. i am going to monitor for a one day. if everything runs perfect, i will check it as resolved. Many thanks again.

joshth said

dom.max_script_run_time changed to 20 prevent accessibility services from accessing your browser box is checked Refreshed and restarted the firefox Nothing is changed, it hangs and freezes after browsing on the websites for a while. IS there a permanent fix to this. i spend many hours trying to fix this issue. i really dont want to uninstall firefox because it is really good compared to the rest. But it is so annoying when trying to browse or watch sports online, when it freezes or lags, ruins the experience. i have firefox 57.0.3 64 Bit installed, i installed it from scratch. Please help me to resolve my issue. im sure Im not alone in this.

Ok, so where is that accessibility services coming from? My own install doesn't pop that message up so what was the accessibility services installed from? I tried looking at the options in FF but don't see something related to Accessibility services.

i have 57.0.3 64 Bit installed so im guessing it came with it.

Your fine. Disregard other than please monitor and you now have the solution if ever need to make changes.

If this solved your issue please mark it solved with solution that did so. Thank You for contacting Firefox Support.

thanks for your help, Pkshadow.