When should a search box be added to dropdown lists?

1. How do I add a search box to a drop down list?

How do I add a search box to a drop down list?

Use any element to open the dropdown menu, e.g. a <button>, <a> or <p> element. Use a container element (like <div>) to create the dropdown menu and add the dropdown links inside it. Wrap a <div> element around the button and the <div> to position the dropdown menu correctly with CSS.