https://www.bleepingcomputer.com/news/microsoft/microsoft-released-windows-10-cumulative-updates-kb4345421-and-kb4345420/

Microsoft has just released new cumulative updates for the Windows 10 Creators Update (version 1703), Fall Creators Update (version 1709), and April 2018 Update (version 1803) to introduce a series of quality improvements.

Build 17134.166 (KB4345421) is aimed at systems running Windows 10 April 2018 Update and it comes with several improvements that you can find below: