[Users] Creating threads manually

[Removed GDPR]

Hi,

There are some cases where actual email discussion
threads are broken up. For example messages exchanged
through ticket based support systems of service
providers often get divided into multiple 2-message
threads although it is really the same discussion.
(sometimes with varying subject due to status changes).

Is there a way to manually combine messages from such
communication into a thread?

-- 
George