Import discards all tasks' labels

[femto-code]

Describe the bug I recently tried importing a backup, generated by v4.7.2 (Snap, for some reason this the latest?) into the latest v4.8.4 (Flatpak). However, once imported, the labels were restored in the labels section but all tasks lost their assigned labels.

Expected behavior Export and import should allow transferring all information including the assigned labels.

Desktop (please complete the following information):

• OS: Ubuntu 22.04 GNOME 42.9 -> Fedora 40 GNOME 46
• Version: 4.7.2 (Snap) (export) -> 4.8.4 (Flatpak) (import)

Additional context I am wondering why the assignment was not restored. I had a look in the backup JSON file and all tasks had their labels as properties properly assigned. 🤔

Thanks for your help!