An extra "x" button exists in the inventory and loading screen

There is an extra exit button in the inventory and on the loading screen

Steps to Reproduce:
1. Load a world.
-> there is an extra "x' button on the top left.

1. Open the Creative Inventory
-> there is an extra "x' button.

Expected Results:
There should not be another exit button.

Observed Results:
There is an extra exit button behind the "All/any category name" texts and ? button, basically on the lower top right corner.