Rated 5 out of 5 stars
Since A$$trali$ came out the referer display is no longer available unless you use Classic Theme Restorer or Vimperator (probably Pentadactyl too).
I think you mentioned here that you didn't want to deal with A$$trali$ but what would be a great idea is to have the referer as the tooltip.
Right now if you hover over the button it just says "RefControl", maybe you can change that to the referer.
Just a suggestion. I use Vimperator so it doesn't matter to me. v32 (currently Beta) puts large back/forward/refresh/bookmark buttons in the right-click menu, so all the millions of people in the world who wear glasses/contacts will soon be able to use Firefox again hassle-free.