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