This adds several handy X11 utilities, such as xrandr, and some other window managers, in order to eventually use a different one and avoid fwvm race conditions.
I think it would be interesting to test with some different WMs than fvwm, at least because they are more commonly used.
Then, I also think that fvwm has some race conditions, and it causes spurious focus loss, as https://bugs.winehq.org/show_bug.cgi?id=54594 for instance. I've been running the same test in a tight loop with any of the other WMs added here (mutter / kwin / openbox) and it is not reproducing. With fvwm the failure reproduces quickly and systematically.
The xrandr utility would be useful in the future, but only after the image is updated to a newer xserver-xorg-video-dummy version which would support multiple screens. It will then be possible to set them up with the following commands:
``` xrandr --addmode DUMMY1 1024x768 \ --addmode DUMMY2 1024x768 xrandr --output DUMMY0 --auto \ --output DUMMY1 --right-of DUMMY0 --mode 1024x768 \ --output DUMMY2 --right-of DUMMY1 --mode 1024x768 xrandr # to refresh the settings ```
Then I think it doesn't hurt to have it installed in the meantime.