Secure clipboard + Windows issue: "Global clipboard contents copied to qube and wiped"

Sometimes (but regular enough to be irritating), Ctrl+Shift+C in a Windows DVM returns a dom0 toast:

“Global clipboard contents copied to qube and wiped”.

Erm, Ctrl+Shift+C Should be copying the qube clipboard contents into Dom0 and the toast should report how many bytes this is. Predictably, I cannot then paste what I copied into another qube.

Workaround: install rdesktop on another qube, enable inter-qube networking (open TCP 3359), connect via RDP, Copy-Paste works consistently.

What threw me off was it only working sometimes in the Windows qube window.