After backing up all my apps and their data, i updated my Lineage OS.
When i restored my Apps, it turned out that i had an CardDAV address book in use that was offline for a long time. Many contacts have been updated in the phone but never been synced. The problem is that i can’t re-establish the account within the new instance of Lineage, because the URL (and it’s server) is dead.
I had no success restoring Contacts, Contact Storage Provider (What does that by the way?), DAVdroid or Accounts.
[Q] How can i restore the contact data of the above mentioned CardDAV address book?
Updating a Samsung Galaxy S5 from Cyanogenmod 12 to Lineage 14.1 - using oandbackup and DAVdroid 1.9-ose