Did you notice the three software buttons in Android 5.0 Lollipop yet? Prior versions of Android have also had a trio of controls but they get a redesign in the latest Google software. And the third one, which is used to switch between open apps is completely different.
The old task switching button used to show a vertically stacked view of open apps. Now, the new Overview button brings up a carousel of cards; each representing an open app. Or an open browser tab. And in the Chrome settings you can modify how the browser tabs are shown: Independently or consolidated.