Visual folder comparison and synchronization
[ О приложении ]

FreeFileSync is a folder comparison and synchronization software that creates and manages backup copies of your important files.
Instead of copying every file every time, FreeFileSync determines the differences between a source and a target folder and transfers only the minimum amount of data needed.

NOTE: Due to technical limitations, FreeFileSync installed from a Flatpak can't read configuration files of your other Flatpak applications, commonly stored at "~/.var/app/".
If you need to process files in that directory, you must use a non-Flatpak installation of FreeFileSync (or some other tool).

NOTE 2: FreeFileSync allows you to open files in external applications or run custom scripts.
However, when sandboxed as Flatpak, external applications or scripts from your host system are not accessible.
However, you can use the Flatseal app to grant FreeFileSync a permission to access "D-Bus session bus", and then it should be possible to run run your app or script if you prefix your command with "flatpak-spawn --host".

Источник
Репозиторий: flathub

FlatPak: FreeFileSync [Utilities]