For Offline transactions new “offline” addresses are supported: it includes all the necessary information for 10 payments so that a receiver doesn’t need to talk to the sender to create a transaction. Once the ten payments run out, the sender wallet will automatically request more payments from the receiver using SBBS. In case the Receiver is not online and not responding, the Sender wallet will show an indication that there are no more payments left and the user will request a new address using an external channel.
Atomic swaps are significantly cheaper now due to SegWit support and a minimal fee rate is nicely recommended so that transactions will complete within a reasonable time.
Confirmation count is implemented for CLI wallet and in the API to better align with exchanges.
Confidential Assets metadata is standardized. Read more here.
Once generated, do not offer the same offline address to multiple senders of payments
Offline transactions do not have payment proofs (to be added in version 5.2)
Points to mention:
Offline transaction fees are higher. The receiver pays his fee (per coin) when the coin is withdrawn from the shielded pool. To keep the anonymity set to the best value at any given time, the max privacy coins may remain in the shielded pool until the receiver decides to spend them. Hence, the withdrawal fee for each coin received via offline transaction can be paid when the receiver initiates the outgoing transaction of his own.
For a more comprehensive list of the tasks accomplished please read here