isNodeInDOM method
Implementation
bool isNodeInDOM(T? node) {
var parents = getNodeParentsUntilRoot(node);
if (parents.isEmpty) return false;
var root = parents.last;
if (isTextNode(root)) return false;
var rootTag = getElementTag(root) ?? '';
rootTag = rootTag.toLowerCase().trim();
return rootTag == 'html' || rootTag == 'body' || rootTag == 'head';
}