JSFiddle - React, Tailwind, and code Playground

HTML

<script src="//tinymce.cachefly.net/4.0/tinymce.min.js"></script>
<textarea id="BodyText"></textarea>

JavaScript

tinymce.init({
    selector: "#BodyText",
    toolbar: "extraquote",
    menubar:false,
    //statusbar: false,
    setup: function (ed) {
        ed.addButton('extraquote', {
            text: false,
            icon: 'strikethrough',
            onclick: function () {
            //    alert(ed.selection.getNode().nodeName);
                 node = ed.selection.getNode(); 
                if (node.nodeName == "STRIKE") {
                   with(document.getElementById('BodyText_ifr').contentWindow){
                           var newElement = document.createTextNode(node.innerHTML);
                    }                    
                     node.parentNode.replaceChild(newElement, node);
                }else{
                    ed.selection.setContent('<aside><strike class="extra">' + ed.selection.getContent() + '</strike></aside>');
                }
            }
        });
    },
});