https://learn.microsoft.com/en-us/dotnet/api/system.diagnostics.process.errordatareceived?view=netframework-4.8.1&viewFallbackFrom=net-7.0
Process.ErrorDataReceived Event (System.Diagnostics) | Microsoft Learn
Occurs when an application writes to its redirected StandardError stream.
event systemprocessdiagnosticsmicrosoftlearn