Please go down the list : '''''To be Checked and turned off unless needed for accessibility : ''''' 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. '''''Multi-Processor Support : ''''' 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. Note : Hardware Acceleration is for Video Card, Monitor to see if remain off or to turn back on. Only Disable as last resort. '''''Multi-processor Can completely disable it this way in about:config :''''' dom.ipc.processCount set to 1 browser.tabs.remote.autostart = false browser.tabs.remote.autostart.2 = false *http://kb.mozillazine.org/About:config Only move to esr if low ram and old system. '''''Firefox Extended Release Version :''''' Firefox ESR does not come with the latest features but it has the latest security and stability fixes. *https://support.mozilla.org/en-US/kb/switch-to-firefox-extended-support-release-esr If do please : *https://support.mozilla.org/en-US/kb/back-and-restore-information-firefox-profiles *https://support.mozilla.org/en-US/kb/export-firefox-bookmarks-to-backup-or-transfer

My memory usage is still to high

You have not tried to disable not move to ESR. You did not take long enough to try those things. Please do so.

Under 1 GB isn't really "too much". How much RAM do you have installed?

I have 4 GB

So it's not really too much. In your case too much is, say 5GB.