For those who don't want to be bothered to dig around on mozilla.org to find the instructions, these are the lines to add to your prefs.js to greatly improve the browsing experience:

user_pref("capability.policy.default.Window.open", "noAccess");
user_pref("capability.policy.allowpopups.sites", "http://www.mozilla.org http://bugzilla.mozilla.org http://www.bakterium.com http://www.gaijin.com");
user_pref("capability.policy.allowpopups.Window.open", "sameOrigin");

You must first close mozilla before adding those lines in order for it to work..

1. Now, copy the above text into a vi window.
2. Close your browser.
3. Edit prefs.js to and paste in the above lines, adjusting specifics to suit your surfing preferences.
4. Reopen browser.

Do it. Now. You'll thank yourself later.

This has been a public service announcement of the Better Browsing Advocacy Agency.