This issue happens every time when closing the menu, and only when "Eternal Promise" is the selected banner when closing it, the other ones don't cause it.
Basically, the game lags a lot for no reason afterwards until you open a different menu, or open the recruit menu again and close it when a different banner is selected. It's usually a 10-20 FPS drop even when I was getting 144 FPS solid before, and it feels much worse than that, with jittery camera movement and such.
It essentially keeps the standard banner screen up in the background until you open a different menu, as it's not clearing the game memory properly.
If anyone knows where the devs will actually see bug reports, feel free