mdn-polyfills/Node.prototype.append.js

MDN polyfills

!function(){function t(){var e=Array.prototype.slice.call(arguments),n=document.createDocumentFragment();e.forEach(function(e){var t=e instanceof Node;n.appendChild(t?e:document.createTextNode(String(e)))}),this.appendChild(n)}[Element.prototype,Document.prototype,DocumentFragment.prototype].forEach(function(e){e.hasOwnProperty("append")||Object.defineProperty(e,"append",{configurable:!0,enumerable:!0,writable:!0,value:t})})}();