So over the years, I've wondered why certain things aren't commonplace features in browsers. One of those is a way to log out of HTTP auth, a long-standing issue with web apps. But it wasn't until recently that, when asked in #web about it, that I actually thought to check if Mozilla did in fact have an interface in its arsenal to do it. Lo and behold, it does.
Since it does exist, I sat down and wrote the world's most trivial Mozilla extension: Clear HTTP Auth. Now, the next time I'm testing HTTP logins, no more closing the browser. At least, not until the time comes to test in other browsers.