Bidirectional replication

[mclei-asw]

We have a bidirectional logical replication. It means, the master DB replicates/sends some data to slave DB and also slave DB sends another data to master DB (it is not master-master, always the different set of data are send in each direction).

For master->slave I can use the standby_slot_names parameter to block sending logical replication data until the standby streaming replica applies and confirms them.

BUT how can I limit the opposite direction? When the standby streaming replica is off, logical replication master->slave are blocked, but data slave->master are happily applied and confirmed back to slave. So the slave can drop its wals.
When I promote the standby replica now, it will not contain the data from slave.