Webtop:ubuntu-openbox container howto change default resolution?


I’m using webtop:ubuntu-openbox by running it using suggested docker command:

docker run -d
–security-opt seccomp=unconfined #optional
-e PUID=1000
-e PGID=1000
-e TZ=Europe/Rome
-e SUBFOLDER=/ #optional
-e TITLE=Webtop #optional
-p 3010:3000
-p 3011:3001
-v /path/to/data:/config
-v /var/run/docker.sock:/var/run/docker.sock #optional
–device /dev/dri:/dev/dri #optional
–shm-size=“1gb” #optional
–restart unless-stopped

It works well , but I would like to change default display resolution which comes in a strange 1406x905.
Despite once started I’m able to change resolution by command (i.e. issuing xrandr -s 1024x768 ) I’m unable to change it at container startup.

I tried to put xrandr command in .xprofile file, also tried to add it in /etc/init.d/x11-common but no success.
Either I’m unable to find where such 1406x905 is set.

xrandr output is :
Screen 0: minimum 32 x 32, current 1406 x 905, maximum 32768 x 32768
VNC-0 connected 1406x905+0+0 0mm x 0mm
1406x905 60.00*+
1920x1200 60.00
1920x1080 60.00
1600x1200 60.00
1680x1050 60.00
1400x1050 60.00
1360x768 60.00
1280x1024 60.00
1280x960 60.00
1280x800 60.00
1280x720 60.00
1024x768 60.00
800x600 60.00
640x480 60.00

Thank you in advance in helping me.

We do this in the steamos image, two places

Xrandr will work but it can also be set here: