Ubports edition shows nothing on screen after liquid exposure

[wibble]

Try the serial console to see what's going on behind the scenes.

Do you have any hardware or software recommendations for accessing the phone through the serial port?

The wiki pages both here and for PmOS describe the necessary hardware :
https://wiki.pine64.org/index.php/PinePh...al_console
https://wiki.postmarketos.org/wiki/PINE6...al_console

A couple of people have blogged about their experiences doing it in more detail than I'll manage:
https://bloggerbust.ca/post/my-first-exp...l-console/
https://dimitris.cc/kde/2020/05/01/USB_S...phone.html

I've got an old 3.3V FTDI USB-serial board that I haven't got round to wiring up to a 3.5mm jack yet, but have used for similar purposes in the past. I find picocom friendlier than minicom,and I've never much liked emacs. The bloggerbust.ca post includes an example of what you should see all the way from the uboot bootloader starting up, through the boot process to a login prompt, and some of the things you can do after login. Remember you need to flip the dip switch to change between headphone and serial console mode!