OmniFocus 4.4.3 just shipped with a bug I found in the change log!
Sync – Fixed issue of the same Mac showing multiple registrations in Settings > Sync > Registered Devices, when running macOS 15 Sequoia. After this update, OmniFocus 4.4.3 may show up as one additional registration; delete all other registrations of the same Mac (that don’t include “this device”) to improve sync times.
I’d been pruning these ghost devices every few days. Happy to not need to look at sync devices now. 🙂