https://roboticsbackend.com/install-ubuntu-on-raspberry-pi-without-monitor/

https://forums.raspberrypi.com/viewtopic.php?t=315089

the raspberry pi imager has some issues you can add invalid characters that make the config invalid…need to check it.

other issues have been reported.

https://askubuntu.com/questions/1249708/connect-raspberry-pi-4-with-ubuntu-server-to-wifi