Trouble making an Ubuntu flavour (dual-boot) USB stick with persistence file(s)

[Ralf Mardorf]

On Tue, 05 Jan 2021 09:24:52 +0100, Ralf Mardorf via ubuntu-users wrote:
>After that I wanted to add persistence by a file as described by
>https://www.ventoy.net/en/plugin_persistence.html , taking into account
>that "The persistent file/partition name in Ubuntu 20.04 has been
>officially changed from  casper-rw  to  writable "
>-
>https://askubuntu.com/questions/1236445/casper-rw-persistence-files-not-working-with-20-04
>by running
>
># /opt/ventoy/CreatePersistentImg.sh -s 6400 -t ext4 -l writable
># mv -i persistence.dat xubuntu-20.04.1-desktop-pers1.dat
>
>This is the used and probably faulty ventoy.json:
>
># cat /mnt/VTOYEFI/ventoy/ventoy.json 
>{
>    "persistence": [
>        {
>            "image": "xubuntu-20.04.1-desktop-amd64.iso",
>            "backend": "xubuntu-20.04.1-desktop-pers1.dat"
                       ^ ^
Maybe I need to add a leading dash to the files?!