KB4580386 is an optional update for v1909 and v1903 systems. Listed here are the direct download links for that KB4580386 offline installer.

Microsoft is on the roll releasing new updates for Windows 10 v1903 and v1903. Just a week ago Microsoft released the security update KB4577671 and now released the cumulative optional update KB4580386 for both v1909 and v1903 system. Unlike the previous update, this can be a non-security update. Which means that the update only contains fixes and enhancements to Windows and its modules. These fixes include but not restricted to the audience Policy module, occasional black screen in Windows Virtual Desktop, general performance issues, Xbox Game Pass, Windows Defender, User Access Control, etc. Quite simply, the KB4580386 update has a lot of standard of living improvements and fixes to visit along with.

Like with any cumulative update, I suggest you wait at least per week before installing. Should there be any bugs in the update, those is going to be ironed out in that point frame. Along as you did not pause the auto updates feature, the update should be installed automatically. If not, you are able to trigger the update process by clicking on the "Check for updates" button on the "Settings → Update & Security→ Windows Update" page.

Alternatively, you may also install the update by downloading the KB4580386 offline installer. You can find the download links for the KB4580386 installer download below.

KB4580386 Offline Installer Download Links

To make things simpler for you, I found the direct download links for KB4580386 for Windows 10 32-bit and 64-bit systems. Depending on your system type, download the update while using below links and do the installation like any other Windows software. After installing, restart the machine and you are all set.

f you would like KB4580386 download links for Windows Server, ARM64 based systems, as well as other version go to the Microsoft update catalog website to find the proper links. All you have to do is click the Download button near the appropriate version.

KB4580386 Change Log

Addresses an issue with using Group Policy Preferences to configure the homepage in Internet Explorer.
Allows administrators to utilize a Group Policy to allow Save Target In terms of users in Microsoft Edge IE Mode.
Addresses an issue with untrusted URL navigations from Internet Explorer 11 by opening them in Microsoft Defender Application Guard using Microsoft Edge.
Addresses an element that occurs when using the full suite of developer tools in Microsoft Edge for remote debugging on the Windows 10 device.
Addresses an element that displays a black screen to Windows Virtual Desktop (WVD) users when they attempt to register.
Addresses an element that might prevent a Microsoft Xbox Game Pass user from playing certain games which are eligible for play.
Addresses an element that displays nothing on screen for 5 minutes or more during the Remote Desktop Protocol (RDP) session.
Addresses a reliability issue that triggers the screen to flash constantly.
Addresses a problem with Dynamic Data Exchange (DDE) that causes a memory leak when multiple clients connect to the same server.
Addresses an element that causes an application to stop responding temporarily, which causes extra z-order operations that affect the Window.Topmost property of a window.
Addresses an element that might cause DDE apps to stop working.
Addresses an element that is the place you first sign in for an account or unlock a current user session using Remote Desktop Services (RDS). Should you enter an incorrect password, the current keyboard layout changes unexpectedly somewhere default keyboard layout. This keyboard layout change might cause additional attempts to register to fail or result in account lockouts in domains with low account lockout thresholds.
Addresses a problem with the CleanupProfiles Group Policy object (GPO). Once you upgrade the operating-system, when you configure the CleanupProfiles GPO, it fails to remove unused user profiles.
Addresses an element that displays an unacceptable CPU frequency for certain processors.
Addresses a performance issue that happens when PowerShell reads the registry to see if the ScriptBlockLogging registry key is within the registry.
Addresses an issue that randomly changes the time offset of the time format returned by the command WMIC.exe OS Get localdatetime/ value.
Addresses an element that prevents Microsoft Consumer experience Virtualization (UE-V) from assigning the Microsoft Outlook Signatures.
Addresses an issue that prevents Hybrid Azure Active Directory joined devices from updating portal information whenever a device name or Windows version changes.
Addresses an element that causes Windows to stop working and generates error 0x17. This problem occurs when Windows Defender Device Guard is enabled and a driver is loaded with a 4K Microsoft Portable Executable (PE) header.
Adds a brand new Microsoft Event Tracing for Windows (ETW) provider named "Microsoft-Antimalware-UacScan". This ETW provider reports the facts from the context for each User Account Control (UAC) request in the ETW provider manifest.
Addresses issue that causes a USB printer port to vanish after restarting once the printer device is turned turn off.
Addresses an issue that causes stop error 0xd1 in msiscsi.sys. This issue occurs when moving certain arrays from one cluster node to another.
Addresses an element that prevents Windows Update and Microsoft Store from connecting to peers over virtual private networks (VPN) for downloads.
Adds functionality that shows a preview of the features and capabilities included in an update whenever a new update is offered to your device. Around the Windows Update page (Start > Settings > Update & Security > Windows Update), there's an option to "See what's within this update."
Adds support for the Transport Layer Security (TLS) 1.1 and 1.2 protocols when connecting to SQL Server while using data providers in Windows Defender Application Control (WDAC).
Addresses a problem with SQL Server that might cause performance issues should you configure a Linked Server provider to load out-of-process.
Addresses an element that might degrade Windows performance and stop the LanmanServer service from starting when third-party software uses LanmanServer custom file system controls (FSCTL).
Addresses a problem with deduplication that triggers long wait times on Resilient File System (ReFS) Cluster Shared Volumes (CSV).
Addresses an issue that might prevent some applications from behaving correctly. This happens whenever you publish them as Remote Application Integrated Locally (RAIL) applications using RDS and alter the docking for an AppBar window.
Addresses a problem having a deadlock within the Transmission Control Protocol/Internet Protocol (TCPIP) driver that causes the operating-system to prevent working or stop responding.
Addresses an issue that causes the Routing and Remote Access Service (RRAS) to stop responding for brand new connections. However, RRAS continues working for existing connections.
Addresses an element that causes the RRAS administrator Microsoft Management Console (MMC) to prevent responding randomly when performing administrative tasks or at startup.
Improves the Windows Server Storage Migration Service by:
Adding inventory validation.
Improving retransfer performance .
Resolving multiple issues, including reliability issues.
Verifying that source machines have installed the current update.

That is it.