The problem is not the engine. It’s the Epic Games Launcher that crashes. If you take a look into the log you should see some
[2025.06.12-20.17.13:880][518] LogCommunityPortalAppManager: RequestAppInstall: Add INSTALL action for artifact Hash:PluginName
[2025.06.12-20.17.13:880][518]LogCommunityPortalAppManager: RequestAppInstall: Inserted UNCHANGED action for main game artifact (null):(null):(null) at index 0
[2025.06.12-20.17.13:883][518]LogWindows: Error: appError called: Assertion failed: IsValid() [File:D:\build++Portal\Sync\Engine\Source\Runtime\Core\Public\Templates/SharedPointer.h] [Line: 890]
I think everybody is affected by this since today. Same reports in UE Discord channels as well.