class Rails::HTML::PermitScrubber

def scrub_node(node)
  # If a node has a namespace, then it's a tag in either a `math` or `svg` foreign context,
  # and we should always prune it to avoid namespace confusion and mutation XSS vectors.
  unless prune || node.namespace
    node.before(node.children)
  end
  node.remove
end