SunEditor

<p>Here is an example of math -> <span class="katex" contenteditable="false" data-exp="\displaystyle\sum_{i=1}^{k+1}i" data-font-size="1.5em" style="font-size: 1.5em;"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><mstyle scriptlevel="0" displaystyle="true"><munderover><mo>∑</mo><mrow><mi>i</mi><mo>=</mo><mn>1</mn></mrow><mrow><mi>k</mi><mo>+</mo><mn>1</mn></mrow></munderover><mi>i</mi></mstyle></mrow><annotation encoding="application/x-tex">\displaystyle\sum_{i=1}^{k+1}i</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:3.1137820000000005em;vertical-align:-1.277669em;"></span><span class="mop op-limits"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:1.8361130000000003em;"><span style="top:-1.872331em;margin-left:0em;"><span class="pstrut" style="height:3.05em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mtight"><span class="mord mathdefault mtight">i</span><span class="mrel mtight">=</span><span class="mord mtight">1</span></span></span></span><span style="top:-3.050005em;"><span class="pstrut" style="height:3.05em;"></span><span><span class="mop op-symbol large-op">∑</span></span></span><span style="top:-4.300005em;margin-left:0em;"><span class="pstrut" style="height:3.05em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mtight"><span class="mord mathdefault mtight" style="margin-right:0.03148em;">k</span><span class="mbin mtight">+</span><span class="mord mtight">1</span></span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:1.277669em;"><span></span></span></span></span></span><span class="mspace" style="margin-right:0.16666666666666666em;"></span><span class="mord mathdefault">i</span></span></span></span> 123</p>
            <div class="se-component se-image-container __se__float-right" contenteditable="false"><figure style="margin: auto;"><img src="http://suneditor.com/docs/cat.jpg" data-align="right" alt="Sunset image" data-rotate="" data-proportion="false" data-rotatex="" data-rotatey="" origin-size="640,426" data-origin="640,426" style="transform: rotate(0deg);" data-index="0" data-file-name="cat.jpg" data-file-size="0" data-size="," data-percentage="auto,auto"><figcaption contenteditable="true" style="margin-top: 0px;"><p>Insert description</p></figcaption></figure></div>
            <h3>The Suneditor is based on pure JavaScript, with no dependencies.</h3>
            <pre>Suneditor is a lightweight, flexible, customizable WYSIWYG text editor for your web applications.</pre>
            <blockquote><p>Supports Chrome, Safari, Opera, Firefox, Edge, IE11, Mobile web browser.</p></blockquote>
            <p><strong><span style="color: rgb(255, 94, 0);">SunEditor</span></strong> <em><span style="background-color: rgb(250, 237, 125);">distributed under</span></em> the<strong> </strong><a href="https://github.com/JiHong88/SunEditor/blob/master/LICENSE.txt" target="_blank">MIT</a><strong> </strong>license.</p>
            <p><hr class="dashed"></p>
            <p><span style="font-size: 16px;"><span style="font-family: Impact;">Table</span></span></p>
            <table style="width: auto;"><thead><tr><th><div>Column_1</div></th><th><div>Column_2</div></th><th><div>Column_3</div></th><th><div>Column_4</div></th><th><div>Column_5</div></th></tr></thead><tbody><tr><td><div><br></div></td><td><div><br></div></td><td><div><br></div></td><td><div><br></div></td><td><div><br></div></td></tr><tr><td><div><br></div></td><td><div><br></div></td><td><div><br></div></td><td><div><br></div></td><td><div><br></div></td></tr><tr><td><div><br></div></td><td><div><br></div></td><td><div><br></div></td><td><div><br></div></td><td><div><br></div></td></tr><tr><td><div><br></div></td><td><div><br></div></td><td><div><br></div></td><td><div><br></div></td><td><div><br></div></td></tr><tr><td><div><br></div></td><td><div><br></div></td><td><div><br></div></td><td><div><br></div></td><td><div><br></div></td></tr></tbody></table>
            <p><br></p>
            <ul>
                <li>Pasting from Microsoft Word and Excel.</li>
                <li>Custom table selection, merge and split.</li>
                <li>Media embed, images upload.</li>
                <li>Can use CodeMirror, KaTeX.
                    <ul>
                        <li>And.. many other features :)</li>
                    </ul>
                </li>
            </ul>
            <p><br></p>