the catalog zone's default primary servers list contained a large
number of items. This has been fixed. :gl:`#5658`
-- Adding NSEC3 opt-out records could leave invalid records in chain.
-
- When creating an NSEC3 opt-out chain, a node in the chain could be
- removed too soon, causing the previous NSEC3 being unable to be found,
- resulting in invalid NSEC3 records to be left in the zone. This has
- been fixed. :gl:`#5671`
-
- Fix slow speed of NSEC3 optout large delegation zone signing.
BIND 9.20 takes much more time signing a large delegation zone with