Comment 104 for bug 60995

Here's the Firefox documentation page which says that on Linux Backspace should take the user back a page in history. Here's the footnote:
"For this shortcut to work on Linux, use about:config to set the preference browser.backspace_action to 0."

The Documentation link:
http://www.mozilla.org/support/firefox/keyboard#f1

Thanks for your attention to this matter. It really is much simpler to just hit backspace button.

The documentation page shows that both IE and Opera also use Backspace to go back in history as well.