On On-premise Domino, this can be changed via;
Disabling replication of unread marks
- From the Domino Administrator, click the Files tab.
- Select the database(s) for which you are disabling the replication of unread marks.
- From the Tools pane, click Database - Advanced Properties.
- Click the "Select" check box to the left of Replicate unread marks and then click the Replicate unread marks check box to remove the check mark from that check box.
- Click OK.