Document.adoptNode() transfers a node from another document into the method's document. The adopted node and its subtree are removed from their original document (if any), and their ownerDocument is changed to the current document. The node can then be inserted into the current document.

## Syntax

### Parameters

externalNode

The node from another document to be adopted.

### Return value

The copied importedNode in the scope of the importing document.

After calling this method, importedNode and externalNode are the same object.

Note: importedNode's Node.parentNode is null, since it has not yet been inserted into the document tree!

## Examples

const iframe = document.querySelector('iframe');
const iframeImages = iframe.contentDocument.querySelectorAll('img');
const newParent = document.getElementById('images');

iframeImages.forEach((imgEl) => {
});

## Notes

Before they can be inserted into the current document, nodes from external documents should either be:

Note: Although Firefox doesn't currently enforce this rule, we encourage you to follow this rule for improved future compatibility.

For more on the Node.ownerDocument issues, see the W3C DOM FAQ.

Specification
DOM Standard