Originally written by Eric Warren at www.gllabs.org
One of the biggest challenges in theme development is making sure your theme looks the same (or at least similar) in all types of browsers. As a general rule, supporting the current production release and one release back of the big 3 browsers (Internet Explorer, FireFox, and Opera) is a good goal to shoot for.
Most folks have automatically upgraded to the latest release of IE (v7), so how do you test for IE6? If you are running XP, you can use the MultipleIE program which allows you to install older versions of IE without breaking your standard install. See http://tredosoft.com/Multiple_IE for more information.
Firefox allows you to have both v2 and v1.5 installed at the same time.
Opera?
If your theme is designed to allow varying number of columns, make sure you test with all three columns, then two and finally with only the main content area. Do this for all browsers you want to support.
Test all the Geeklog admin screens. Make sure the Admin Home link renders properly in each browser.
Remember, Geeklog has 3 types of stories, featured, normal and archived. Each of these has their one set of templates. Make sure all three properly display.
Test the major Geeklog plugins. I would recommend that test your theme with the following popular plugins: