I use the arrow keys to control movement.
I have my Run key set for Right Shift.
I have my Inventory set for Enter.

If I am holding the Run key, and press the Inventory key (Shift+Enter) at the same time the GUI will crash. Inventory will open as normal, but the Hotbar and meters are not visible. Behavior same as pressing F1. However, pressing F1 at this time does not turn it back on. There is no way to get it back, short of exiting and reloading.

Holding Run and pressing Inventory Open, Inventory Close (Shift+Enter, Shift+Enter; pressed quickly... basically hold Right Shift and press Enter Enter quickly is what I'm saying)
causes the game to soft-crash. The world is no longer visible, but Inventory is still functional. GUI still missing, obviously.

Pressing Enter, Enter quickly at this point crashes to desktop.

I am consistently able to replicate this issue.

It was difficult to graphically represent this bug. Hopefully my explanation was clear.

I attempted replicating this error from a friends computer, unsuccessfully. However, he uses WASD with E for Inventory.