This article https://blog.hagander.net/another-couple-of-steps-on-my-backup-crusade-235/ states that temporary replication slots can be "used to prevent the wal on the server from being removed while a downstream replica or backup still needs it"
Apparently, temporary replication slots can now be used by pg_basebackup since 10. My question is how do we enable this feature or does it happen now automatically with pg_basebackup?
Also, is this feature related to the -X stream option "Stream the write-ahead log while the backup is created. This will open a second connection to the server and start streaming the write-ahead log in parallel while running the backup. Therefore, it will use up two connections configured by the max_wal_senders parameter. As long as the client can keep up with write-ahead log received, using this mode requires no extra write-ahead logs to be saved on the master." which is enabled by default? https://www.postgresql.org/docs/current/static/app-pgbasebackup.html