Last modified: 2014-10-01 12:44:57 UTC
The #jump-to-nav links are currently hidden using "height: 0; overflow: hidden;", and that's causing trouble with absolutely positioned elements, like coordinates (especially in the Vector skin). This makes the coordinates position change in Firefox, depending on whether these links are present in the HTML or not (they are always present in the source for anonymous users, but not for logged-in users). To reproduce, visit [[de:Berlin]] in Firefox 23, logged out (-> coordinates appear above header line) and logged in with #jump-to-nav links disabled (-> coordinates appear below header line). This is rather new; the coordinates are meant to be below the header line at all times (and it used to be like that). I'd suggest to hide them with "position: absolute; top: -9999px;" like it is done in vector/screen.css for #mw-navigation h2. That should achieve consistent behavior across browsers.
Thanks for the report and the detailed analysis!
