[Users] See the 'FILES' section of `man claws-mail` for brief descriptions of the files.

[Removed GDPR]

Thanks Colin.

Yes, I think understand the process of deletion. My
confusion is/was rather about what happens if a message deleted on the
server gets restored from backup locally, i.e if it will be re-uploaded
to the server thus creating a duplicate (one copy in inbox/folder and
another in Trash).

Similarly it is not completely clear if restoring from backup a local
cache file would prevent the proper synchronization. That depends on
the program logic. For example the following logic would prevent the
sync (pseudo code):

if (local_cache_file_exists) {
    // Do not sync
} else {
    // Fetch new items
    // Update tags for existing items
    // ...
}

--
George