UWP name parameter with period

Getting a string resource from a resx file (satellite assembly) under UWP with this API (Xamarin.Forms called in a .NET Standard 2.0 assembly), if the name has a period in it this will return null (must have at least two satellite assemblies to see it). It can be retrieved using forward slash. If resource is "foo.bar". this works as the name parameter on .NET Framework 4.5.2, under UWP [Microsoft.NETCore.UniversalWindowsPlatform 6.0.1] this will return null. Passing "foo/bar" will successfully get the resource, but only under UWP. I don't know if this is a documentation bug or a bug in the platform - feel free to let me know so I can raise a bug in the proper place. Similar issue with Windows.ApplicationModel.Resources.ResourceLoader as per https://stackoverflow.com/questions/28505933/using-resourceloader-getstring-method-to-retrieve-resources-with-dots-in-the-key

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* ID: 7ed0db74-37fc-7273-4eda-6ab47240c225
* Version Independent ID: 85def6f3-06ec-08c9-ae68-4d85a286583b
* Content: [ResourceManager.GetString Method (System.Resources)](https://docs.microsoft.com/en-us/dotnet/api/system.resources.resourcemanager.getstring?view=netframework-4.7.1#System_Resources_ResourceManager_GetString_System_String_System_Globalization_CultureInfo_)
* Content Source: [xml/System.Resources/ResourceManager.xml](https://github.com/dotnet/dotnet-api-docs/blob/master/xml/System.Resources/ResourceManager.xml)
* Product: **.net**
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* Microsoft Alias: **dotnetcontent**