Gmail: Delete an Individual Message in a Threaded Discussion
Contributed by Rob Rogers 
Tagged: Google If you have unrelated emails embedded in a threaded discussion in your Gmail inbox, you can delete them without removing the other emails in the thread.
1. Select the desired thread from your Gmail Inbox.
2. Select the email that is to be deleted from the thread.
3. Go to the upper-right corner of the email, select the dropdown arrow to the right of Reply.
4. Select Delete this message.
The message will be removed from the thread.
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