Firefox supports integrated domain authentication on windows. The big difference between it and other browsers like IE and Chrome is that in Firefox you have to whitelist every domain you'd like it to authenticate to.
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It's also not a shipping browser, of course... yet.
Midori 0.1.2 ships with a copy of webkit that will render Acid3 100/100. Admittedly though, it is lacking in many other respects.
Since when do they speak English in France?