Unable to find the details of bug fix in 9.6.x minor version.

I am seeing in postgresql release notes that below bugs are fix in 9.6.x version but unable to find the details for about that bug .

Fix unexpected timeouts when using wal_sender_timeout on a slow server (Noah Misch) .

1. A new server parameter data_sync_retry has been added to control this; if you are certain that your kernel does not discard dirty data buffers in such scenarios, you can set data_sync_retry to on to restore the old behavior.

2. Fix logic for stopping a subset of WAL senders when synchronous replication is enabled

3. Make the archiver prioritize WAL history files over WAL data files while choosing which file to archive next

Ensure that temporary WAL and history files are removed at the end of archive recovery.

Avoid unwanted delay during shutdown of a logical replication walsender. 

Fix failure in logical replication publisher after a database crash and restart

This can eliminate many attempts to fetch non-existent WAL files from archive storage, which is helpful if archive access is slow.

Regards,

Sameer Malve