JSFiddle - React, Tailwind, and code Playground

HTML

<div class="boundary">1</div>
<div class="boundary">2</div>

JavaScript

$(document).ready(
    function () {
        var state = {flag: false};
        $('.boundary').mousedown(function () {
            state.flag = true;
            console.log(state);
        });
        $('.boundary').mouseup(function () {
            state.flag = false;
            console.log(state);
        });
    }
)