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User-Agent: Mozilla/5.0 (X11; U; Linux i686; rv:1.7.3) Gecko/20041016
Firefox/0.10.1

Description of problem:
When configured to "display windows from all workspaces", the Window
List applet does not display the names of windows on the 2nd head of a
system set up with Twinview.  If you drag the window from the 2nd head
to the 1st head, the window title appears when you drop the window.

For the purposes of this explanation, "1st" head refers to the head on
which the panel is placed.  The two heads are combined into one
spanning desktop (i.e., windows can stradle the border between the two
heads.  Interestingly enough, the window only shows up in the Window
list when the window is more than half on the 1st head.

Also interesting -- if you put a panel on the 2nd head, all windows --
regardless of head -- are listed!

After doing a "killall -HUP gnome-panel", the window lists are still
out of sync, but the 1st head has all windows listed, and the 2nd head
is missing windows on the 1st head. 

Version-Release number of selected component (if applicable):
gnome-panel-2.8.1-2

How reproducible:
Always

Steps to Reproduce:
1. Set up a dualhead display using Twinview
2. Put a panel on both heads, put a Window List applet on both heads
3. Set both panels to display windows from all workspaces.
4. Open windows on both heads, move them around a bit

    

Actual Results:  The panels get out of sync.

Expected Results:  The panels should always agree.

Additional info: