Timeline feature not grouping messages together

Timeline feature not grouping messages together

I just started a trial of TeamInbox.

I composed a new email in TeamInbox and sent it to my personal gmail account. I received it in gmail successfully, and it was properly delivered from the shared inbox email address. So far, so good!

I then replied to the message in gmail.

My reply appeared in the TeamInbox, but as a new message, not as a reply to my message. I expected my reply to show up "under" the message I composed in TeamInbox and to start a "timeline". (Similar to the "conversation view" in other email programs.)

Is there some setting that controls this?