Adding .NET Standard libraries to 4.7.1 lib adds loads of references, some broken

The answer I'm creating for my own question is:

Does your .NET Framework project use packages.config ? If it does, DO NOT reference .NET Standard libraries. The package/reference/binding-redirect in VS 2017 is horribly broken if you introduce .NET Standard. Trying to fix it will cause more problems (I've wasted several days trying). Expect to have assemblies which don't load despite being present, lots of warnings and a broken app.

If you use System.Net.Http, plan on spending several days in Google and GitHub issues trying to get that to work.

If you are able to upgrade to packageReferences, this should fix the problem. But if your project contains packages that import content, like JQuery or Bootstrap be aware that these no longer work and you'll instead spend more time trying to fix those references and migrate to npm or bower, along with fixing TypeScript compilation too. No thanks.

Ideally you'd be using the 2017 csproj format but that's not compatible with WinForms, ASP.NET or Windows Services - so tough if you've got a legacy project.

Because of some issues with the implementation of the .NET Standard 2.0 support on .NET Framework 4.7.1, additional files are required to be deployed to your bin folder.

This issue is described as a known issue here.

The number of files copied to the output folder will be 0 when you are targeting or running on .NET Framework 4.7.2.

Please also make sure you are using the latest Visual Studio (at least version 15.6.3) because some of the changes required to make this scenario work are available there.