ubuntu persistence version 20.04 in legacy mode

[longpanda]

When use persistence you don't need to replace the config file to add some persistence boot option.
So just use

Code:

{
    "persistence" : [
        {
            "image": "/ISO/ubuntu-20.04.1-desktop-amd64.iso",
            "backend":"/persistence/20.04.dat"
        }
    ]
}

and make a try.

Besides, 
1. does it prompt you to select to boot with or without persistence data when you select the ISO to boot?
2. How did you make the persistence data file?