To demonstrate an issue with TabbedPage
Run the project. Click the "Open Tabbed Page" button A tabbed page opens, with two pages - Page 1 and Page 2. Page 1 is displayed (no content in this example though), and the bar is under Page 1 to highlight it is the current page. Click Page 2, the bar will correctly disappear from under Page 1 and appear under Page 2. Click the Back button to close the page. Click the "Open Tabbed Page" button. Now both Page 1 and Page 2 titles have bars under them! In fact only Page 1 is shown, and therefore only Page 1 should have the bar under it!