[winswitch] Windows not appearing in task manager

[Douglas Doole]

Since upgrading to xpra 0.15.x (both .0 and .1 have this problem) I've had
trouble with windows not appearing in the task manager. (xpra 0.14.x never
had this problem.)

For example, I'll start one konsole over xpra and it will appear in the
task manager. Yet when I start a second konsole it appears on screen, but
not in the task manager. Unfortunately I haven't been able to pin down a
pattern to which windows appear in the task bar and which ones don't.
(Today, the first window I created showed up in the task bar and the rest
are not. I do not, however, have consistent good luck with the first window
created.) The problem does not seem to be tied to a specific application.
(I mostly use konsole and gvim, but I've seen the problem with other
applications as well.)

As I'm playing with things and writing this note, I see that it's having
more trouble than I originally thought. I have now also seen an existing
task manager entry disappear as a new window is created. The task manage
entry for the new window may or may not be created.

My client and server are both running Ubuntu 14.04. My client is using KDE.

I have tried starting with client with "-d window" but it didn't report
anything. Is there a different debug option I should use?

Thanks.