I think there is a bug: I was trying out the Clipboard feature, but I don't seem to be able to Delete/Paste items from the clipboard. If I try to delete an item, it always comes back if I click again on the "clipboard" button. and if I click Paste, nothing happens.
I'm using Firefox 37.0.1 and Windows 7.
In case it matters: I installed the following add-ons:
- Chat Reply Helper for Stack Exchange sites
- Firebug
- Greasemonkey
- Web Developer toolbar