Return from SMS and restore the black bar

When I click on the Chrome app version of Join, there is a black bar across the top that says, "Devices Notifications SMS/Phone." Then when I click "SMS/Phone" I see all my messaging threads. I click on one to detail into the thread, and it has an arrow at the top to return back to where I was. However the black bar is no longer visible and the only way I've found to get it back is to exit and re-enter the app. My idea is to allow the user to go back and have the black bar menu. Thanks!