Shadow-looking background on comments #163
Description
There's a weird shadow-looking horizontal bar under comment titles on the ticket page:
It's not a box-shadow (that would have been caught by the noshadows.py script), this time it seems to be a fancy CSS background. Disabling the background completely looks a bit too empty, so I'm not sure how to replace it (maybe a simpler line rather than a gradient?).
We should also try to figure out if other elements are affected.