JSFiddle - React, Tailwind, and code Playground

HTML

a: <input type='text'/><br/>
b: <input type='text' onkeyup="if(!tabPressed){ alert('This is it !'); }"/><br/>

JavaScript

var tabPressed = false;
document.addEventListener('keydown', function (e) {
    if(e.keyCode == 9) {
        tabPressed = true;   
    } else {
        tabPressed = false;
    }
}, false);