Can I run a bash script before I configure Ubuntu when I start it first time? I couldn’t find, but maybe I missed it. If I configure it, then run my script and then clone, the clone will inherit the user, language etc settings which I don’t want

Sorry I thought it was the same. I think I came across this before and it seemed a bit too complex for my level but I will give it another go

Thanks - I will give this a go if I can’t find a solution for customizing without firing up the os

Yes, this is what I use to flash the image to the SD card. The issue is that I want to change the official image before flashing and that is where I’m stuck