Update links.

Author: MikeRayMSFT

docs/sql-server/what-s-new-in-sql-server-ver15.md

@@ -49,13 +49,17 @@ In addition, the following features are added or enhanced for [!INCLUDE[sql-serv
 |Register external languages|New DDL, `CREATE EXTERNAL LANGUAGE`, registers external languages, like Java, in SQL Server. See [CREATE EXTERNAL LANGUAGE](../t-sql/statements/create-external-language-transact-sql.md). |
 |More supported data types for Java|See [Java data types](../language-extensions/how-to/java-to-sql-data-types.md).|
 |Custom capture policy for the Query Store|When enabled, additional Query Store configurations are available under a new Query Store Capture Policy setting, to fine tune data collection in a specific server. For more information, see [ALTER DATABASE SET Options](../t-sql/statements/alter-database-transact-sql-set-options.md).|
-|[In-memory database]() adds new DDL syntax to control the hybrid buffer pool. A trace flag is no longer required to enable the hybrid buffer pool.|With [hybrid buffer pool](../database-engine/configure-windows/hybrid-buffer-pool.md), database pages sitting on database files placed on a persistent memory (PMEM) device will be directly accessed when required.|
+|[In-memory database](../relational-databases/in-memory-database.md) adds new DDL syntax to control the hybrid buffer pool. <sup>2</sup>|With [hybrid buffer pool](../database-engine/configure-windows/hybrid-buffer-pool.md), database pages sitting on database files placed on a persistent memory (PMEM) device will be directly accessed when required.|
+|New in-memory database feature, memory-optimized tempdb metadata added.|See [Memory-Optimized TempDB Metadata](../relational-databases/databases/tempdb-database.md#memory-optimized-tempdb-metadata)|
 |Linked Servers support UTF-8 character encoding. |[Collation and Unicode Support](../relational-databases/collations/collation-and-unicode-support.md) |
 |`sys.dm_exec_query_plan_stats` returns more information about degree of parallelism and memory grants for query plans. |[sys.dm_exec_query_plan_stats](../relational-databases/system-dynamic-management-views/sys-dm-exec-query-plan-stats-transact-sql.md)<sup>1</sup>|
 | &nbsp; | &nbsp; |
 
 ><sup>1</sup>
 >This is an opt-in feature and requires [trace flag](../t-sql/database-console-commands/dbcc-traceon-trace-flags-transact-sql.md) 2451 to be enabled.
+>
+><sup>2</sup>
+>A trace flag is no longer required to enable the hybrid buffer pool.
 
 ### [!INCLUDE[master-data-services](../includes/ssmdsshort-md.md)]