Serious bug: inputs are broken in 2.81 when the game is started with a DirectInput controller plugged in.
The controller may not be supported (fair enough) but that leads to a weird mix where the mouse controls the cursor's position, which can hover and highlight menu items but not click, and the controller button #1 controls the clicks. Controller axes do nothing and the mouse buttons do nothing.
I did navigate the options with that combination of mouse and controller and did not find an option to disable the controller.
Then I exited the options and the continue / codex entries were overlapping for me too.
It is very unusual for a game to completely disable its keyboard support, and I would strongly recommend against it.