mate-desktop/mate-window-manager — pull request #10 by stefanct (2012-08-23 14:43:15+00:00)
Title: Allow alt+tab etc while drag'n'drop is active

This is still not fixed "upstream" (i.e. in metacity) but many distributions
ship with this patch. The patch is from Matthias Clasen (Redhat).
See https://bugzilla.gnome.org/show_bug.cgi?id=135056#c33 and
https://bugs.launchpad.net/ubuntu/+source/metacity/+bug/111939
for details.

I missed this feature since i changed from ubuntu's gnome 2 to mate,
so i googled the cause... and well, here it is. I have NOT TESTED this though!