Forum:Monobook logo has disappeared

At w:c:tardis, our monobook logo — i.e. the one defined by — no longer appears on pages. I can't figure out what happened. There's just nothing appearing on the top left of our pages, when viewed in monobook. I've taken a few steps to resolve this, but nothing's worked. I've moved the original contents of to, then deleted wiki.png and started over with a completely fresh start to the page. I've looked in Firebug to see if the page is referencing the correct file. Hovering my mouse over the style definition for that part of the page reveals the new logo, so I'm guessing it is referencing the correct URL. I've changed the new logo several times, ultimately bringing it down to the exact recommended width for monobook of 135px.

None of this has done anything.

I notice that other people's wikis still seem to be happily displaying the contents of wiki.png, so it's definitely something about our wiki that's at fault. Anyone have any ideas/memories about how to make a hidden monobook logo reappear? 15:40:28 Sat 11 Jun 2011