swap 2 dom elements code

src/js/gui/widgets/Utils.js

@@ -4,4 +4,15 @@ Element.prototype.insertChildAtIndex = function(child, index) {
     } else {
         this.insertBefore(child, this.children[index])
     }
-};
+};
+
+Element.prototype.swap = function (node) {
+    const parent = this.parentNode;
+    const sibling = this.nextSibling === node ? this : this.nextSibling;
+
+    // Move `this` to before the `node`
+    node.parentNode.insertBefore(this, node);
+
+    // Move `node` to before the sibling of `this`
+    parent.insertBefore(node, sibling);
+};