What is a duplicate thread and how do I mark one in Zoho TeamInbox?

What is a duplicate thread and how do I mark one in Zoho TeamInbox?

When a client sends an email to two different email addresses, the email will appear in both inboxes, causing confusion for team members who may not realize that the email has been duplicated.
To mark a thread as duplicate:
 1. Login to Zoho TeamInbox.
2. From the left pane, select the team and the inbox.
3. Navigate to the thread and click More actions from the top bar.
4. Select Mark as duplicate.