On Desktop, select a user in the world.
Show the author of their avatar using the button on the right side, and press escape while on the menu to return to playing.
You are now softlocked and must restart the game.
You are no longer able to move and your mouse doesn't work. You can still bring up your pause panel with ESC, however there is no way to actually use it as your mouse is frozen in place.
Voice chat still works correctly for both you and others, and if a player walks past your cursor you are still able to click on them while paused to bring up their profile. It seems the UI still functions correctly when this occurs.
I have tried this on two separate computers to make sure it wasn't a local issue.
Is this already known? It's very frustrating.