I have 2 HDMI touchscreens that I'd like to have with identical vertical displays. By identical, I mean I'd like the screens to be mirrored and show exactly the same image.

The Screen Layout Editor is not working for this. I am able to rotate the screens. I am able to drag them around as long as they don't overlap. I am asked to reboot each time I make a change.

As soon as I stack them on top of each other in the layout editor and reboot, they default back to the default horizontal side-by-side configuration. What am I missing to make them display the same thing?

I have an older Pi 4 that I've done this successfully with so I know its do-able. It is also what is recommended all over the internets. Any help is appreciated.

Lastly, I attempted to install a new OS and was able to reproduce this problem on a fresh OS install.

Edit: I dug up an old image that I have that works with same hardware. Working one is running buster and the one that is not working is on bullseye. Can someone please point me to some config that I should look at that may be different? Looking at /boot/config.txt the only difference seems to be dtoverlay=vc4-kms-v3d vs dtoverlay=vc4-fkms-v3d(working), but changing this property does not fix the issues.

1 Answer 1


I have run into a similar issue with Bullseye, but it doesn't even ask me to reboot. It does apply the changes I make, but any time I reboot, it does not remember the settings and I have to reconfigure it every time.

I worked around this issue by using xrandr.

  1. I built the xrandr command that would set the screens the way I wanted (ref: https://x.org/releases/X11R7.5/doc/man/man1/xrandr.1.html ; archived: https://archive.ph/JNVsl)
xrandr --output HDMI-1 --primary --mode 1024x768 --rate 60.00 --output HDMI-2 --mode 1024x768 --rate 60.00 --right-of HDMI-1
  1. I added a script to the GUI start up script area (ref: https://www.makeuseof.com/how-to-run-a-raspberry-pi-program-script-at-startup/ ; archived: https://archive.ph/qskAf)
sudo nano /etc/xdg/autostart/display.desktop


[Desktop Entry]
Exec=xrandr --output HDMI-1 --primary --mode 1024x768 --rate 60.00 --output HDMI-2 --mode 1024x768 --rate 60.00 --right-of HDMI-1

Now when I reboot, after the GUI loads, it runs my script and puts the monitors in the configuration I want.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.