To Speed Up your Firefox browsing just follow these simple steps.
Open a new tab on firefox and type the about:config on the address bar.
Then new Window will appear, now Right click on anywhere whitespace on your window and click New > Integer
New Pop up Window will appear. Then Type the nglayout.initialpaint.delay
on the box then click Ok.
After that new window will appear. then Enter 0 Value then restart firefox
Hope You will See Good Result..