The IETab extension isn't "tabs like IE", making an IE7 upgrade equivalent. The extension takes a normal Firefox tab, loads the MS WebBrowser activex control into it (instead of the Firefox xul:browser element that uses the normal Gecko engine), then tells that control to load a URL. So you're using the IE engine, inside Firefox. (Note, however, that I don't think it does anything extra for security: AFAIK, you're still completely at the mercy of any IE bugs.)
If you upgraded to IE7, you'd have to use it for everything. This way, you can use Firefox for everything that works with it, and IE in a tab for the few things that don't. |
