JSFiddle - React, Tailwind, and code Playground

HTML

<div id="timers">Timers</div>

JavaScript

$('#timers').data('firsttimer', 100);

//prints 100
document.write("<b>" + $('#timers').data('firsttimer') + "</b>");

function blah(){
    //Prints nothing
    document.write("<i>" + $('#timers').data('firsttimer') + "</i>");
}

blah();