Speed up and tweak Firefox with these tips
Speed up the Firefox browser
I had problems with Firefox being slow on Facebook, but this tip has helped. Go to about:config and search for this value.
Change this to false and this will speed up Firefox.
This is another value that will help speed the browser up.
The new cache will be enabled and you should get a speed boost and a smoother browsing experience.
Disable Firefox telemetry
Firefox also has telemetry built-in. This tries to connect to the https://incoming.telemetry.mozilla.org URL to report usage of the browser. This can be blocked with the about:config settings below.
Adding the URL to the blocked site settings in your router if possible would also block this telemetry.
To provide a small speed boost for web browsing, change these two values in about:config to true.
This will give a small boost to Firefox when browsing the Internet.