JSFiddle - React, Tailwind, and code Playground

HTML

<script src="https://igniteui.com/js/modernizr.min.js"></script>
<script src="https://code.jquery.com/jquery-1.9.1.min.js"></script>
<script src="https://code.jquery.com/ui/1.10.3/jquery-ui.min.js"></script>
<script src="https://cdn-na.infragistics.com/igniteui/latest/js/infragistics.core.js"></script>
<script src="https://cdn-na.infragistics.com/igniteui/latest/js/infragistics.lob.js"></script>
<link href="https://cdn-na.infragistics.com/igniteui/latest/css/themes/infragistics/infragistics.theme.css" rel="stylesheet"></link>
<link href="https://cdn-na.infragistics.com/igniteui/latest/css/structure/infragistics.css" rel="stylesheet"></link>

<div id="htmlEditor"></div>

CSS

#htmlEditor {
            margin-bottom: 10px;
        }
        #feedback 
        {
            padding-left: 10px;
            color: Red;
        }
        span.ui-icon.ui-icon-insert-email
        {
            background-image: url("https://igniteui.com/images/samples/html-editor/ui-icons_222222_256x240.png")!important; 
            background-position: -192px -128px;
        }
		/* Override sample's browser styles */
    	#htmlEditor h1, #htmlEditor h2, #htmlEditor h3, #htmlEditor h4, #htmlEditor h5, #htmlEditor h6 { margin: 0px; }
    	#htmlEditor h1 { font-size: 1.9em; }
		#sampleContainer { overflow: visible; }

JavaScript

$(function () {
            var height = $('html').hasClass('touch') ? 500 : 350;
            // initialize igHtmlEditor
            var htmlEditor = $("#htmlEditor").igHtmlEditor({
                width: "99%",
                height: height,
                inputName: "htmlEditor",
                customToolbars: [
                {
                    name: "EmailSignature",
                    collapseButtonIcon: "ui-igbutton-collapse",
                    expandButtonIcon: "ui-igbutton-expand",
                    items: [{
                        name: "appendSignature",
                        type: "button",
                        handler: appendSignature,
                        scope: this,
                        props: {
                            isImage: {
                                value: false,
                                action: '_isSelectedAction'
                            },
                            imageButtonTooltip: {
                                value: "Insert e-mail signature",
                                action: '_tooltipAction'
                            },
                            imageButtonIcon: {
                                value: "ui-icon-insert-email",
                                action: '_buttonIconAction'
                            }
                        }
                    }]
                }]
            });
        });

        function appendSignature(ui) {
            var currentContent = $("#htmlEditor").igHtmlEditor("getContent", "html");
            var signature = "<p>Best regards,<br/>John Doe<br/>Acme Corp<br/>555-1111</p>";
            $("#htmlEditor").igHtmlEditor("setContent", currentContent + signature, "html");
        }