I have been having 3 issues with the EPIC launcher recently. Which may be symptoms of the same problem.
Issue 1 - After minimizing the launcher. The launcher will occasionally make itself visible again with the friends list being open and visible.
Issue 2 - After minimizing the launcher. The launcher will occasionally create an invisible window that blocks mouse clicks. With the position and size matching what the launcher was using before it was minimized.
Issue 3 - After minimizing the launcher. When you make the launcher visible again. It will often not be scaled or positioned correctly. It will often reappear only partially visible because it is positioned outside of the monitor viewport.