Alternatively, projects that use .NET SDK can set PreserveCompilationContext build property to true. Publishing such project will copy reference assemblies for the framework the project targets to a refs sub-directory of the publish directory.
I used < PreserveCompilationContext > true < / PreserveCompilationContext > and published the WEB application, but I didn't see the refs subfolder. How do I use the refs tag?

A quick trace though the code indicates that you also need to add:
<MvcRazorExcludeRefAssembliesFromPublish>False</MvcRazorExcludeRefAssembliesFromPublish>
By default the web sdk disables the refs folder, because it would otherwise always be generated due to internal details of how razor view pre-compilation works.
Adding that property tells the web that you really do want the refs folder.
This probably does need to be better documented.
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A quick trace though the code indicates that you also need to add:
By default the web sdk disables the refs folder, because it would otherwise always be generated due to internal details of how razor view pre-compilation works.
Adding that property tells the web that you really do want the refs folder.
This probably does need to be better documented.