There's no need for clipman's icon in the panel when the clipboard is empty, it just waste space. Hiding clipman's icon would help to reduce panel clutter. It should unhide when something is copied to the clipboard. Thanks for your hard work... Francisco.
That concept might be interesting for other plugins too. I don't think clipman would be the first plugin hiding itself when it is "idle", but it is an interesting feature to add. The only problem is once the plugin is hidden, it won't be possible to reach it at all, so no properties dialog, no ability to drop etc. You have to be 100% sure about what you are doing when you activate such an option. IMHO it doesn't waste that much space, it's just a small button, it's not like the taskbar for instance.
Thanks for your answer Mike. In order to unhide clipman you would have to copy something to the clipboard again, but that may seem a little unpractical, and doesn't allow to drag and drop to clipman when it's empty either... so i gess your right. Thanks for your time, and good luck with XFCE 4.6 release!