What is the eqvivalent to Jquery focusout() in Vanilla JS?

I am rewriting a jquery function and I would like to know how to write the jquery focusout function in vanilla?

var inputBox = $('.searchbox-input');
// ...
inputBox.focusout();

>Solution :

You can use dispatchEvent as a (near) equivalent to jQuery’s trigger.

document.querySelector('.searchbox-input').dispatchEvent(new Event('focusout'));