Introduction onboarding reappears after rotating screen

Steps to reproduce:

Create a new account
Add two test contacts
Open one of the conversations
The introduction onboarding is shown (as expected)
Dismiss the onboarding by pressing the back button or tapping inside or outside the circle (doesn't matter which)
Rotate the screen
The onboarding is shown again (bug)
After leaving and re-entering the conversation, the onboarding isn't shown again (as expected) - this suggests it's an issue with the ViewModel

Tested on the Moto G 4G (Android 5.1).