Editors Note: The first version of this post contained a section criticizing what appeared to be a major regression concerning dropDatabase and movePrimary commands. It was found out that it was merely a documentation error in the MongoDB 4.2 release notes, which is now fixed: https://jira.mongodb.org/browse/DOCS-12474. The (In)Stability section is now removed. At Percona weve [&]

https://www.percona.com/blog/2019/08/16/long-awaited-mongodb-4-2-ga-has-landed/