Using Windows a lot has got me in the habit of using the backspace key to go back a page when browsing the internet.
Firefox does not enable this behavior by default in Ubuntu – fortunately it is not too hard to configure.
Open Firefox and then type about:config as the URL and then press Enter. You’ll see a nice large warning:
Click I’ll be careful, I promise to continue.
Type browser.backspace_action in the filter until browser.backspace_action is the only item that you see below.
Double-click on the browser.backspace_action preference and change the default value of 2 to 0 (zero).
This setting will take immediate effect.
Source: My Digital Life