Custom Checkboxes/Radios Do Not Display Correct Color on :focus For Validation

Created by: Joyrex

In the documentation: https://getbootstrap.com/docs/4.0/components/forms/#supported-elements

Tab or via dev tools set :focus on custom radio or checkbox and outlined focus state is default color instead of the appropriate validation state color. Also, should the appended and prepended elements (like the Browse button on the custom file input) show the proper validation state colors? Seems a bit off having only the input part of the element styled.