Currently, if a DataTemplate is created from an Element rather than from the Resources Panel, they are generated without a visible 'DataType' Property in Studio.
(They are however assigned one in the XAML)

This lack of a visible type makes it difficult for a user to determine why certain DataTemplates are not appearing as valid Templates for usage on certain Elements, and also makes it difficult to understand that the DataType is something that should be cleared if the user wants to use it as a 'Universal' Data Template.

See attached image.

Repro Steps:

1) Create a Studio Project featuring a MainPage.xaml
2) Introduce a ListBox Element to the Page
3) Right-click on the ListBox, and from its Context Menu, navigate to Templates-->ListBoxItem-->Create Template.
This will open the Template in the Template Dummy Editor.

4) Navigate to the Resources Panel, identify the DataTemplate created in Step 3), and select it.

5) With the DataTemplate selected, navigate to its Properties Panel.

Observe how there is a blue outline around the 'Data Type' Property, but that the field itself is blank.

6) Open the Resources Dictionary in XAML.

Observe how the Template is assigned a Data Type of 'String'.

Expected Results: The assigned Data Type assigned by creating a Data Template in Studio, successfully appears in Studio's Resources interface.