syncing iMessage on MacBook and iPhone
For some time I don't see iMessage incoming messages on my MacBook Pro. I checked the preferences and indeed, the syncing option on my MacOS 10.13.6 is not there. I can send new Messages from my Mac but do not receive them on my Mac. I can send and receive on my iPhone XR with iOS 12.2. Both devices are signed into the same iCloud account. Proof: everything else (contacts, notes, emails, etc.) syncs perfectly between the two devices.
MacBook Pro 13", macOS 10.13