Feature request: Direct Message chat head pinning

I propose the ability to pin chats like messages in chats and servers. It would prevent them from being closed without first unpinning them, or at the very least prompt with a confirmation for doing so rather than just closing that instant. It would keep the pinned chats above the rest of your open chats, sorted in either recent chats like normal or in order of being pinned. It would also display a little icon on the chat head indicating that it has been pinned. I think that it would be quite nice as there are some chats that I don't want closed and at times close them by mistake whilst mass closing a bunch of open chats.