https://www.w3schools.com/jsref/met_node_insertadjacentelement.asp
HTML DOM Element insertAdjacentElement() Method
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html domelementmethod
https://www.php.net/manual/es/domelement.insertadjacentelement.php
PHP: DOMElement::insertAdjacentElement - Manual
Inserta un elemento adyacente
phpdomelementinsertadjacentelementmanual
https://www.php.net/manual/de/domelement.insertadjacentelement.php
PHP: DOMElement::insertAdjacentElement - Manual
Insert adjacent element
phpdomelementinsertadjacentelementmanual