When both server and client are version 1.0.6 (1.0.6-r15847-2) on ubuntu 14.04 64 bit, clipboard, enabled as bidirectional, works normally.
However, when the server is upgraded to 1.0.7 (1.0.7-r16697-1), while the client remains the same, the clipboard does not work. No error message was found in the log. The only clipboard relevant flag is on the server side: XPRA_CLIPBOARD_LIMIT=30.
This sounds like r16687 might be causing problems again..
This was originally applied in r16414 (fixed up in r16425 for macos and win32) then disabled in r16524 because it broke the clipboard.
If that was the case, you should be seeing this message in the log:
Warning: sanitizing invalid gtk selection type atom %#x
Will try it in a VM.
The backport was incomplete and broke things, r16757 fixes that.
this ticket has been moved to: https://github.com/Xpra-org/xpra/issues/1625