What is causing this warning?
Where you use the code ? Forms project , specific project or library ?
It came from creating Multiplatform library with single-codebase and switching from Net Portable to Net Standard in Target framework and adding the Xamarin.Forms NuGet.
I think it is somehow caused from Net Standard only can be selected up to 1.5 in the project options.
I upgrade Net Standard to 2.0.3 in packages, but issue persists , consider reporting issue on github or seeking further help here : https://support.microsoft.com/en-us/hub/4343728/support-for-business
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