Bug on webapp when

[xWoodIsLife]

Hi, I found a bug on the webapp: When the back button is pressed in a chat on mobile, that chat continues to mark notifications as read.

Steps to reproduce:

1. On mobile, enter a chat, then press the back button to go back to the side panel view.

2. On another account, send a message into that chat

3. On the mobile screen, the notification will disappear and the message will be marked as read, even though the user is in the side panel view and not the chat screen.

This seems to be fixed when I add this.leave(this.state.topic); to the onclick of the hide-message-view button in the messages-view.jsx.

[Gene]

Would you mind sending a pull request?

Thanks!