This is a feature request. I would like to be able to have panels to be on the desktop - that is - underneath all windows. I don't want to have to turn auto-hide on. I have tried the disable-struts setting so that panels don't hinder windows maximising fully, but the panels still sit on top of the window, blocking menus and so on. Thank you.
Not something for the panel, more for widgets on the desktop if we'll ever support this.
I would also like this. I was trying to use transparent panels as a "poor-man's desktop widget" for stuff like notification icons, but realized that it could only work if there was an option to have them always underneath other windows rather than on top.
It would greatly help in using the panel in deskbar mode together with the beos like window style. So that you can basically achive something like that when maximizing a window: http://www.abload.de/img/overlaphnrmr.png And then can click on the in this case ZevenOS Button (which is simply the main menu button on the xfce4-panel) to bring the panel in front. Currently it looks like that when maximizing: http://www.abload.de/img/not_overlapuwp3y.png So as you can see it is using much space on the right and forces the browser in this case to show less information.
Don't think we'll ever fix this in the panel.