The black bars not appearing is intentional, there is a toggle in the settings for them appearing normally in gameplay.
I meant I would like to remove those black bars completely, if there is such a way. 😄
I'm glad they don't appear during gameplay, but only in the menu. But they still look a little weird, that's why I was asking.
I saw that there's a “Disable borders” in the settings. I tried turning it on and off, but in any case nothing changed and the borders were still there.