Simple Vanilla js approach for copying text of data attribute on click

copyToClipboard.js

document.querySelectorAll('.copy-text').forEach(function(elem) {
    elem.addEventListener('click', function() {
        var copyText = this.getAttribute('data-copyText');

        copyToClipboard(copyText);
    });
});

function copyToClipboard(text) {
    var selected = false;
    var el = document.createElement('textarea');
    el.value = text;
    el.setAttribute('readonly', '');
    el.style.position = 'absolute';
    el.style.left = '-9999px';

    document.body.appendChild(el);
    if (document.getSelection().rangeCount > 0) {
        selected = document.getSelection().getRangeAt(0)
    }

    el.select();
    document.execCommand('copy');
    document.body.removeChild(el);
    if (selected) {
        document.getSelection().removeAllRanges();
        document.getSelection().addRange(selected);
    }
};