I’m fairly new to Flatpak and have started to use it more as a reliable way of staying up to date. I am using Linux Mint and the repos are well behind the current version available via Flatpak. My current copy (78.13.0) was originally installed via direct download.
I discovered today that it’s available via Flatpak. What I am concerned about is whether installing via Flatpak will install over my current setup or nuke it and start afresh. I’ve looked at the Thunderbird help and I cannot find any help for my issue.
Flatpaked application lives inside of its own container. So Thunderbird’s configurations will not be stored in your system’s /etc, ~/.config, or whatever else. Instead, they will be stored in the application’s folder it can’t escape, which you can access at ~/.var/app/org.mozilla.Thunderbird. Thunderbird only has read&write access to your Downloads folder, nothing other than that.
P.S. Each app specifies its permissions in its flatpak manifest. They’re shown in GNOME’s Software (since 41) on the app’s page. Flatpak’s cli also lists them when asking for confirmation to install (and probably in some other way, too).