here is the full output
root@baceix:/home/yunohost.backup/archives# tar -tvf /home/yunohost.backup/archives/immich-pre-upgrade1.tar ‘apps/immich/backup/var/www/immich/app’ | grep start.sh
tar: apps/immich/backup/var/www/immich/app: Not found in archive
tar: Exiting with failure status due to previous errors
root@baceix:/home/yunohost.backup/archives#
it seems the Backup doesn’t have a start.sh