Bug in keeping tab history

Bug exists in the latest beta. To reproduce browse http://codepen.io/ionic/pen/AGnqc, example.
Open ‘About’ tab, click on ‘Tab Nav Stack’ to open new view, return to ‘Home’ tab, open ‘Scientific Facts’. Return to ‘About’ tab.
Expected result: ‘ab Nav Stack’ must remain opened. Actual results: ‘About’ index view is opened instead

If you try this again, everything will be fine and history will be kept this time.