MichaelJohn
Well, in my case, in the contacts list app, I have no associated accounts. In "Settings -> Accounts" there are no "Accounts for Owner"
In Signal, I do not allow access to my address book. So, right now, there are no "linked accounts" in my contacts list app; I unlinked them all and removed all duplicates.
But there are multiple problems here. First of all, even if somehow CalDav was importing from Signal, why would there be 50 duplications of a contact?
Secondly, I had over 200 such entries that had "linked" duplicate entries. The "linked" entries did not come from Signal; they were just duplications of the entry in CalDav. I couldn't even tell you how or when the duplications occurred.
I don't copy the entries from one phone to another, so that couldn't be the explanation of how the duplications were created.
In Signal, I have a list of conversations. I do not have any contacts list. But even if I did, I'm not aware of Signal writing entries to CalDav.
CalDav is the only 'original source' of contacts in my case. Any conversation I start in Signal would use the information in CalDav. CalDav never 'imports' any entries from Signal, and, as I said earlier, Signal has no contacts list.
In sum, I don't believe there should be duplications. I cannot see how this is not a bug.
And forgive me if I'm misusing the term "CalDav" versus "contacts list app." I'm looking up CalDav right now to understand exactly what this term means...