Windows 10 Pro Optional Features Missing

Attempting to apply the XPS Viewer feature to a non domain Windows 10 1903 Pro install logged in as a local user results in no features available to select.

Settings_Apps & Features_Optional Features

At this point UAC prompts for elevation, enter the admin account credentials.

Some Optional Features appear along with an Add a feature button.

Click "Add a feature" and again and enter the admin credentials at the UAC prompt.

No features to install appears but it looks optimistic because there are spinning spots which seem to indicate that any minute now the features you are looking for will appear for selection.

But no.  These are not the features you are looking for, user scum.

The spinning spots stop and there is nothing.  Move along.

The problem here seems to be the UAC hand over to the admin credentials.

If you interactively logon as the administrator and carry out the same procedure, the features you are looking for will appear for your selection and installation delight.

Note: The RSATs are Windows 10 optional features but also available for download here
https://www.microsoft.com/en-us/download/details.aspx?id=45520