While there are tons of addons that you can install in Firefox to minimize its memory usage, sometime you may just want to use a simple method without installing yet another extension. Since Firefox 22 there is a native feature that allows you to quickly minimize the memory usage of Firefox.
1. Open your Firefox browser and type “
about:memory” in the URL bar.
2. In the page that show up, you should see a “Minimize Memory Usage” button. If you hover your mouse over it, you will see a description of what it does. Basically, it will trigger a global garbage collection and flush the various cache.
When it is done cleaning up the memory usage, it will show a message “Memory minimization completed”.
Note: You won’t see any effect on a freshly open browser. However, on a browser that have been opened for a long time and has many active tabs, you should see that your Firefox is taking up lesser resources now.