Installing Mobian --> "Resizing file system" forever

[dukla2000]

To install Mobian on an SD card I, all I theoretically have to do is to download mobian-pinephone-phosh-20210314.img.gz, write it to the card, put the card into the phone and start it, right?
...

Yup.

Usually when I have problems with a new image it is because my writing to the disk has had a glitch (as opposed to a corrupt download or a corrupt unzip).

What I would suggest is do the unzip and write in 2 separate steps. So zcat first and you should get an image that is a very round number in size (38000... bytes). Then the dd. Make sure you sync after each step.

Also AFAIK there is no benefit to using the 20210314 image as opposed to the latest nightly. So if you do download again grab the latest nightly unless you have a specific reason for wanting an old image.

Luck