Wikimedia Bugzilla is closed!

Doesn't out default one (/trunk/phase3/skins/common/images/ajax-loader.gif) have a transparent background that could be used?

s/out/our/

Problem is, animated GIFs only have a 1-bit alpha channel for transparency, so each GIF can only be anti-aliased to a single color. PNGs have 8-bit alpha channels and thus no uglyness, but you can't easily animate PNGs. There are 2 different solutions available:

1. Create several different animated GIF spinners - each anti-aliased to a different color.

2. Create a non-animated PNG spinner, and spin it with some fancy javascript/css. Unfortunately this doesn't work in Opera and some older browsers.

1. For multiple backgrounds -- I made these at http://www.ajaxload.info/ so that's easily done

2. No, this is not worth it. 

Another option:

3. eliminate the grey tint block that goes on alternating rows.

Fixed in r85489.