I just tried sending two by clicking “show desktop site” and they ended up being public (which may have caused some confusion)
When you make a new conversation there will be a line saying: “everyone can view this conversation.” If you click change then you can enter the names of the people you want to pm.
Picture attached here, for reference.
1 Like
Thanks. You got my pm that started as a public post for some reason, right?
Yep. 
1 Like