facebookpalm

function createElementFromHTML(htmlString) {
  var div = document.createElement('div');
  div.innerHTML = htmlString.trim();
  return div.firstChild; 
}

const markup = `
    <span>
        <style>
        data-testid="reaction_facepalm" {
            background: '#67a22d';
            border-radius: 50%;
        }
        data-testid="reaction_facepalm":hover {
            transform(scale(1.1))
        }
        </style>
        <span aria-pressed="false" aria-label="Facepalm" class="_iuw _iuy" data-testid="reaction_facepalm" href="#" role="button" tabindex="-1">
        <div class="_39m _1ef2" data-reaction="facepalm">
            <div class="_39n">
                <div class="_1ef0" style="display: inline-block; line-height: 0; font-size: 0px;">
                    <img width="39" height="39" src="https://emojipedia-us.s3.dualstack.us-west-1.amazonaws.com/thumbs/120/facebook/158/face-palm_1f926.png" style="width: 39px; height: 39px;">
                </div>
                <div class="_d6l">
                    <div class="_4sm1">Facepalm</div>
                </div>
            </div>
        </div>
    </span>
</span>`;

const element = createElementFromHTML(markup);

const reactionMenu = document.querySelector('[data-testid="UFIReactionsMenu"]');

reactionMenu.append(element);