This occurs when using a proprietary piece of software called Greenhils MULTI. It seems to be a gtk2 app(?). Certain actions cause dialogs to pop up and more often than not, these cause the program to freeze. It does not freeze, however, when being used with VNC or regular X11 forwarding.
I've also tried it with Xdummy, and the results are the same.
I will attach the log with "-d all" enabled. If I had to guess, I would say the problem corresponds to this part of the log which constantly repeats once the freeze occurs:
2012-11-02 20:46:15,585 x_event_filter event=('wimpiggy-cursor-event', None)/100 2012-11-02 20:46:15,586 Cursor event received 2012-11-02 20:46:15,586 event was delivered to window itself 2012-11-02 20:46:15,586 forwarding event to a XpraServer handler's wimpiggy-cursor-event signal 2012-11-02 20:46:15,587 forwarded 2012-11-02 20:46:15,587 not forwarding to Wm handler, it has no wimpiggy-cursor-event signal
I regret that this is only happening with proprietary software, and therefore, realize it may be difficult to debug with the log alone since the maintainers won't be able to reproduce first-hand.
There was a recent fix to the focus code, please see xpra/handbrake: strange behavior
Are you really using trunk version?
"xpra --version" reports v0.7.1
I tried both 0.7.2-1 and 0.8.0-1 as found here, and I'm having the same issue: http://xpra.org/beta/precise/main/binary-i386/
example app showing focus problems with dialogs
Without being able to test the application in question, there isn't much more I can do on this..
I've added an example of an application which we should handle better regardless (the dialog should not lose focus to its parent) - maybe this is related? Maybe the app does not expect events in the other window until the modal window closes?
r2046 adds proper support for modal dialogs.
Please try and let me know if that improves/fixes things. There are updated ubuntu precise packages here (same build number as before though - other distros will follow).
Note that there may be problems when running multiple apps through the same xpra session - I haven't looked yet.
r2046 had no impact.
Not much else I can do then... Unless you can provide me with a test case, I will have to close this ticket.
this ticket has been moved to: https://github.com/Xpra-org/xpra/issues/204