[starwed]

That's weird -- the icon is still there, but not default, and it just takes about two clicks to restore it.

So what's the purpose of the addon?

[ck2]

You mean the icon in customize? You cannot put that one inside the urlbar.

[starwed]

Aha, all is now clear. (I really liked the idea of the RSS button when they added it, but never actually ended up using it...)