Created attachment 4886 A tiny (yet awesome) 1x27 pixel image which I was using under Zenwalk. Back when I was using Zenwalk with GNOME2 (today MATÉ) I could make a panel transparent by drag 'n' drop transparent images without using composition. This can be good for those, like me, who use composition merely for transparent panels and for those who have a video-card that can not handle or is not handling with composition properly. With the following image, intended for GNOME2, being used with xfce4-panel, I am getting a black background under it. http://gnome-look.org/content/show.php?content=106497
Maybe related: https://bugzilla.xfce.org/show_bug.cgi?id=9510
This works now in >?4.14