Earlier this year, Microsoft shipped Service Pack 1 for .NET Framework, with built-in ClickOnce support for Firefox! Apparently, the .NET update automatically installs this added Firefox addon that’s difficult to remove, because, Microsoft has disabled the "uninstall" button on the extension. What's more, Microsoft tells us that the only way to get rid of this thing is to modify the Windows registry, an exercise that -- if done imprecisely -- can cause Windows systems to fail to boot up.