The numbers in bubbles the resources panel’s sidebar are positioned one pixel too high, so they are not centered. See screenshot. This is a regression from Safari 4.0.4, presumably due to fixing the typo in the font family name (Helvetia -> Helvetica).
Created attachment 47796 [details]
Created attachment 47805 [details]
Specify line-height for the bubbles
Fixed in <http://trac.webkit.org/projects/webkit/changeset/54118>.