The problem with it is that it only fires once and there is no way of checking if it has fired already, so we may register functions that never get called!
(more so with the new osx menu code in #228)
Fixed for trunk in r10708. Closing and added to wiki/Versions/PendingFixes (not sure we want this in earlier versions since no-one complained about it)
this ticket has been moved to: https://github.com/Xpra-org/xpra/issues/991