Currently, a quite important Property of a TabItem is the 'Selected' Property.
However, it is currently hidden-from-view in the Expander section of the TabItem category, whilst also happening to be the only item in the expander.

Therefore, it should probably be taken out of the Expander section, and exposed by default.

See attached image.

Repro Steps:

1) Create a Noesis Studio Project featuring a MainPage.xaml
2) Introduce a TabControl to the Page
3) Select any of the pre-populated TabItems within the TabControl.

4) Attempt to find the TabItem's 'Selected' Property.

Observe how its critical feature is hidden within a hard-to-find expander containing only this Property.

Expected Results: The TabItem's 'Selected' Property is visible at the top-level of the Element's Properties without requiring a section expansion.