Firefox Tweak- minimum memory usage

-Just 9 easy steps-
1. On the website url toolbar type about:config
2. A page full of words will come up. Now right click anywhere and choose New -> Boolean
3. For the name input type “config.trim_on_minimize” .....
4. Select True
5. Restart FireFox.
6. Ctrl + alt + del (this opens your task manager)
7. Go to process and choose your Firefox process (usually called firefox.exe)
8. Look at the Memory Usage Column (average is 25,000-45,000)
9. Now minimise firefox and you will see the memory usage to be less than 15,000