Hi Kevin Burton,
Since it was related to the ASP.NET Core app, you know that it has his own support forum, if possible, please post questions in the ASP.NET forums:
https://forums.asp.net/
In addition, some documents also shared how to create the ASP.NET core app in MAC, you could see them here, maybe it really changed certain features in the specific VS for MAC.
https://docs.microsoft.com/en-us/aspnet/core/tutorials/first-mvc-app-mac/start-mvc
https://docs.microsoft.com/en-us/aspnet/core/tutorials/first-mvc-app-mac/
Anyway, you would get dedicated support from the ASP.NET forum.
Thanks,
Jack
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