Microsoft released the January 2019 Patch Tuesday updates to Windows 10 last week and they have now pushed out another update via Windows Update. It contains a fix for a bug that was preventing some applications from displaying the Help (F1) window correctly. The new cumulative updates are available for April 2018 Update and Fall Creators Update machines, but there is nothing for those who are on Windows 10 October 2018 Update. No new features are being introduced in this update. The fixes include an issue in Microsoft Edge that fails to trigger the focusin event if the focus event listener of an element shifts focus.
Source: https://www.bleepingcomputer.com/news/microsoft/windows-10-version-1803-cumulative-update-build-17134556-released/