This looks like the zoom memory, where, by default, the zoom setting is remembered per site (and across sections). It is a new feature in Firefox 3.
To check, you can reset the zoom for donationcoder.com (Ctrl+0, or View > Zoom > Reset)
-dmtrs
that's it all right dmtrs, thanks

strange that it decided to resize one site and not most others - or not in f0dder's Firefox for example !!
Just checking: so if I set zoom to 120% for dc, yes, it
does remember ...
I would reckon it was previously at about 110% or less (-I work with scales so I'm a good guage

) and when I clicked on the tab it
jumped back to 100% (or 10% less

)
anyways, sorted now, thanks