As you see in the screenshot i changed the "Switch next Tab" keybind to "E" because "R" was feeling weird.
Now i cannot apply changes to any setting anymore because pressing E goes to the next tab. I already clicked the "E Apply" with my mouse, which still does the same -> i get to the controller settings tab.
The big problem here is that clicking the button "Apply" in the settings seems to just simulate the keybinding instead of executing the "apply" action.
Now i'm not a game dev, but seems like the function is called on click "apply"