Firefox 2 has an annoying new "feature" in that if you hit the backspace key, it acts as if you hit the back button on the browser. While I can imagine cases in which this would be useful, in practice it turns out to be really annoying. Often, when I go to the address bar to edit a URL and I start hitting the back key, if I failed to get the cursor in the address bar correctly, I am now taken back several pages in my browsing history. Man I hate this.

Luckily, this behavior can be modified. Here's how:

1 - In the address bar type: about:config.

2 - Scroll down to the entry called browser.backspace_action.

3 - Double-click on this row and it will pop up a dialog box asking you to enter a value. The current value will be 0, change it to be 2 then click OK.

That's all there is to it