I think updates to DOMElement are also necessary. For instance it should be updated so the class reflects that it now implements DOMParentNode, DOMChildNode. Going based off changes noted here php/php-src#4709, I've compiled this list of the items needing updates to class synopsis:

• DOMElement needs implements DOMParentNode, DOMChildNode
• DOMDocument needs implements DOMParentNode
• DOMFragment needs implements DOMParentNode
• DOMCharacterData needs implements DOMChildNode

All the affected items will also need to be updated so the class synopsis includes the appropriate references to the inherited methods from the respective interfaces. I'm guessing that this would be OK for them to all link back to the interfaces docs for the method.

Merge along with: #839

Thank you for the PR! It might make sense to add some further methods to the see also sections, e.g. DOMNode::appendChild comes to mind. I'm not quite sure about the usage of "current node"; AIUI, this refers to $this, so perhaps makes that more explicit.

Thank you!