Change the Debug properties of ASP.Net Core project programmatically by EnvDTE

Question

I'm having a Visual Studio Extension, that change the start Up properties to Debugging a class library. The Extension let the Developer change the Commandline arguments by clicking so he don't have to code all Arguments by hand.

But for normal Class Library Projects it just works fine. but with ASP.Net Core for the

<TargetFramework>net4.8</TargetFramework>

i can't access the Properties anymore.

CurrentProj.ConfigurationManager.ActiveConfiguration.Properties.Item("StartAction").Value = 1; // Launch external programm
CurrentProj.ConfigurationManager.ActiveConfiguration.Properties.Item("StartProgram").Value = "D:\xxx.exe"
CurrentProj.ConfigurationManager.ActiveConfiguration.Properties.Item("StartArguments").Value = "start -a -b1 -lo 5"

any ideas. the Old known way doesn't work for this

Change the Debug properties of Visual Studio project programmatically by EnvDTE

the ASP.Net Core project is using the LaunchSettings, adding one or chaning one is not the problem. but then how do i get/change the selected launchSetting ?.