REDUCE RAM USAGE,WHEN MOZILA FIREFOX IS MINIMIZED
Reduce RAM usage when Firefox is minimized
This setting will move Firefox to your hard drive when you minimize it, taking up much less memory. And there is no noticeable difference in speed when you restore Firefox, so it’s definitely worth a go.
Again, go to about:config, right-click anywhere and select New > Boolean. Name it
config.trim_on_minimize and set it to TRUE.
You have to restart Firefox for these settings to take effect.