a11y util

focus-testing.js

document.body.addEventListener('focusin', (event) => {
    console.log(document.activeElement)
})

style.css

.visually-hidden { 
    border: 0;
    clip: rect(0 0 0 0);
    height: 1px;
    margin: -1px;
    overflow: hidden;
    padding: 0;
    position: absolute;
    width: 1px;
}