For some weeks DavDroid is unable to detect shared address books in Tine 2.0. If it is already detected/synced (old install with updated DavDroid) it just works.
Other sync software such as CardDAV-Sync (Android app) or vdirsyncer (Python script) just detect the shared address books.
Deleting the account(s) and/or DavDroid app (incl. reboot after deinstall) does NOT solve the problem. Tested on three different devices (Samsung Galaxy A5 2017 with Samsung-Android /Moto G with Lineage OS-Port / Samsung Galaxy Tab 2).
Debug log does not include a hint to these shared address books.
"https://TINE20-BASEURL/addressbooks/shared/" shows me the shared address books.
Did you try with DAVdroid 2.0.4? There have been changes in resource detection. Otherwise, it would be nice if you could send a test account to play@bitfire.at, so that I can have a look without preparing a Tine server first.
All devices have DAVDroid 2.0.4-ose. At least the Samsung A5 was updated from 2.0.x as one try in my tests.
I'll send you test account data as soon as possible.
Thanks for the test account! I have found out that Tine produces different responses for different User-Agents.
Note that the response contains /tine20/addressbooks/5403d1e2bd563a912415c7ec5adb9a7c2b66a1d5/3a1e3f348ee6698c517161c63e1707856c29a315/, which is the shared address book.
Note that the shared address book is missing!
which synchronizes as expected (only in one direction, maybe the address book is read-only but not marked as read-only)?
Can you report this to Tine and then give us feedback here?