I can't find the icon for this anwhere on the "private messages" page. At least not one that's clickable.
How do you do it if you only know the username of the person but you can't find a post by them?
Find a post or reply from the person you wish to PM, then left-click on that person's screenname (it should be in blue, like a link) - you'll see a dialog with a menu item to PM that individual.
Search for the username. Should work.
This.
search for the username first. you will then see that user's posts.
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