As a noob who has run into this issue, I’ll just quickly lay out for other noobs how this solved the problem for me:
- Run
sudo setcap cap_dac_read_search=+ep /opt/KopiaUI/resources/server/kopia
This does not provide any output.
- Launch Kopia UI the regular way via your Gnome launcher or any other way you do it.
Kopia UI can now back up root files.