Add width:100% utility class

Created by: Mevrael

Is there a helper to set a width: 100%? I'm currently making an autocomplete input and using .dropdown-menu as base style, however, I can't find a class to make dropdown full width.

Also some bs4 elements are set to display: none by default and I can't find helper to make element visible while there is helper to make element invisible. What are bs4 recommendations on how to do it?