Wikimedia Commons and the English Wikipedia have customized their site-wide CSS to put a checkered pattern on the transparent part of files on the file description page. Because I view this code as almost necessary on any wiki that supports uploading PNGs, I filed a bug about including it in the default site-wide CSS: https://bugzilla.wikimedia.org/show_bug.cgi?id=26470 There's definitely missing functionality here. On wikis that don't use a checkered background, a lot of users end up downloading the images to their computer to look at them in order to determine if a background is white or transparent. That sucks. There was previous discussion about this, but more discussion is needed, apparently. Is site-wide CSS the best way to do this? Would a toggle on the file description page make more sense? User preference? MZMcBride