There’s nothing throughout the installation procedure that will trouble the average user. A synchronization program’s job - FreeFileSync in this case - is very similar and in essence it allows you to keep two folders synchronized, so you can use it as a backup solution and keep copies of files in another place, or you can use it as a way to save yourself from manually making changes twice (one time for each folder).

Keeping backups of your data doesn’t mean that you should only use a backup software to create and update backups in secure places. 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'.' Free backup and synchronization software' However, when sandboxed as Flatpak, external applications or scripts from your host system are not accessible. NOTE 2: FreeFileSync allows you to open files in external applications or run custom scripts. If you need to process files in that directory, you must use a non-Flatpak installation of FreeFileSync (or some other tool).

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/'. 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. FreeFileSync is a folder comparison and synchronization software that creates and manages backup copies of your important files.

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