Why don't websites work in Firefox?

I'll tell you why so many websites don't work with Firefox, Opera et all (more than a fifth of the people using my Canadian websites are using these). Because the webdesigners are too darn lazy to code for and test in any browser except Internet Explorer - you know the one that people use if you ask them WHAT they use and they haven't a clue. They don't even know there is a choice. For the rest of the world who have discovered better software, you're nearly out of luck unless you do a lot of legwork. Firefox at least offers an adddon "ietab" that allows you to mimic Internet Explorer. The bad news is that is exposes you to all the same security issues you were trying to get away from by NOT using Internet Explorer.

Here is a short list of sites I have embedded into "ietab". Some are surprising!

Web Services:
http://secunia.com/*
http://windowsupdate.microsoft.com/*
http://*.spaces.live.com

Financial, Utilities:
http://*.tdcanadatrust.com/*
http://www.ecare.bell.ca/*
https://secureq.bell.ca

Municipal:
http://webcam.city.ottawa.on.ca/*
Business:
http://marinasontario.com