Function isContainerMarkedAsRoot

docs/external/js/react-dom.development.js:7951–7953

(node)

    node[internalContainerInstanceKey] = null;
  }
  function isContainerMarkedAsRoot(node) {
    return !!node[internalContainerInstanceKey];
  } // Given a DOM node, return the closest HostComponent or HostText fiber ancestor.
  // If the target node is part of a hydrated or not yet rendered subtree, then
  // this may also return a SuspenseComponent or HostRoot to indicate that.
  // Conceptually the HostRoot fiber is a child of the Container node. So if you