Created attachment 3335 Screenshot of the workspace switcher When I attach my external 24" display to my 12" laptop, the screen is expanded to the additional screen. The panel is expanded, too, but unfortunately the workspace switcher is expanded, as well and becomes to wide. - Maximized windows are not filling the whole desktop in the switcher (see screenshot) - When I de-attach the external monitor, the workspace switcher is not getting smaller again, this means on the 12" laptop display it will cover half of the panel so there is hardly space for the tasklist left.
We use the wnck pages for this, so not much i can do about it... However if you unplug the 2nd screen and run xfce4-panel -r, does it become normal again?
This is really two reports: 1) Workspace switcher turns wide. I think that's unavoidable if you want to display individual windows in the switcher (it's not a bug, it's a feature). 2) Switcher does not turn narrow anymore. As of today on Xubuntu 16.04 Xenial, I do not observe that behaviour (fixed/can't reproduce).
The switcher going wide is in fact a feature, because it shows both monitors. The reason it doesn't go narrow again is because X doesn't detect the monitor being removed. This can easily be confirmed by running 'xrandr' from the command line. As a workaround, the second output can be turned off by running: $ xrandr --output $PORT --off where $PORT is the xrandr name of the display port you want to turn off.
Closing this bug as invalid, as there never really was a bug (and even with gtk3/libwnck3 we still cannot control that behavior *at all*).