I’m going to switch from Windows 11 to Linux soon but first I wish to backup every every data and config files I can in my current Windows installation, even those that wouldn’t natively work in Linux. I know the \Users folder is important to back up, but I don’t know what other directories I am missing.
\Username\Appdata\Roaming includes the Firefox profile and Thunderbird E-Mails, which you can restore on Linux AFAIK.
Not sure if your Steam folder can be copied over, as well.