Display sent responses for emails I have responded to

[Defenso-QTH]

Is your feature request related to a problem? Please describe.
In my INBOX list, I can identify e-mails I have replied to thanks to a little arrow next to the sender's name.
However, finding my response, for instance to send a reminder, is cumbersome: I need to go to the Sent folder and search again.

Describe the solution you'd like
I would love for SnappyMail to display my response below or over the received e-mail. Like in GMail or Outlook.

Describe alternatives you've considered
A quick and dirty workaround would be to have a button that lets me jump to the response.

Additional context
I have threads activated. It doesn't seem to do anything about this?
Algortihm is set ot REFS. I have no idea what that means, see: #1819