Error Testing Restored Databases
When testing (executing the PowerShell command Test-ContentDatabase) a restored content database in the SharePoint 2016 farm, an error message similar to this may be received:
Database [wss_content_21822_EBS] has reference(s) to a missing feature: Id = [4822d9ca-c6b1-46ab-993a-89a9cfb4e4ac],
Name = [StoragePoint], Description = , Install Location = [StoragePoint].
It is because the externalization was not set to No before performing the content database backup on the SharePoint 2013 farm. It doesnt prevent the database from being mounted or upgraded.