JSFiddle - React, Tailwind, and code Playground

HTML

<form id="dialog-form">
    <div class="expand">
        <button>Expand</button>
    </div>
    <div class="addSubClass">
        <button>Add Sub-Class</button>
    </div>
    <input />
</form>

JavaScript

$("#dialog-form *").on("focusout", function () {
    setTimeout(function() {
        if ( $(document.activeElement).closest('#dialog-form').length === 0 ) {
            console.log('form has lost focus');
            //Do some stuff...
        };
    }.bind(this));
    
});