ERROR: must be superuser or replication role to use

Set the maximum WAL size for replication in the Max slot wal keep size setting The value of this setting can be edited as of PostgreSQL ver

With the change in Postgres 16, when you're on a standby, you can actually create a logical replication slot There are a few mechanics around

postgres replication slot To enable this feature, you need to call the pg_create_logical_replication_slot() function or use the CREATE REPLICATION SLOTLOGICAL command

postgres delete replication slot This blog introduced you to PostgreSQL Logical replication slots, their purpose, and the step-to-step setup introduction