Best answer by Maryam
As far as I know, it does not allow you to delete a conversation completely. What I mean is that you can only delete your own sent messages in a conversation one by one, not the other person's messages.
Here are the steps:
- Click your profile icon on the top right corner of the screen.
- Click "Private messages".
- Open the conversation.
- Place the mouse pointer on the … icon.
- Hit Delete.
Hope this helps.