Hi @Hartmut ,
Welcome to Microsoft Q&A!
I tested it on my side. I suppose it is designed like this.
As this document described:
/Command: Starts the IDE and executes the specified command.
/Edit: Opens the specified files in a running instance of this application. If there are no running instances, it starts a new instance with a simplified window layout.
The /edit can be used in the existing instance or no running instance.
But for /command, every time it will first launch the VS, then executes the specified command.
If a VS instance has been opened, running “devenv /edit /command” will go to the most recently opened instance. but the /command requires launching a new instance. So it doesn’t work,
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