fix(Popper): add null & connected checks for document (#12284)

Author: kmcfaul

packages/react-core/src/helpers/Popper/thirdparty/popper-core/dom-utils/getDocumentElement.ts

@@ -7,5 +7,5 @@ import { Window } from '../types';
  */
 export default function getDocumentElement(element: Element | Window): HTMLElement {
   // $FlowFixMe: assume body is always available
-  return (isElement(element) ? element.ownerDocument : element.document).documentElement;
+  return ((isElement(element) ? element.ownerDocument : element.document) || window.document).documentElement;
 }

packages/react-core/src/helpers/Popper/thirdparty/react-popper/usePopper.ts

@@ -35,6 +35,17 @@ type State = {
 
 const EMPTY_MODIFIERS: any = [];
 
+function isReferenceConnected(reference: Element | VirtualElement): boolean {
+  if (reference instanceof Element) {
+    return reference.isConnected;
+  }
+  const { contextElement } = reference;
+  if (contextElement instanceof Element) {
+    return contextElement.isConnected;
+  }
+  return true;
+}
+
 export const usePopper = (
   referenceElement: (Element | VirtualElement) | null | undefined,
   popperElement: HTMLElement | null | undefined,
@@ -114,6 +125,10 @@ export const usePopper = (
       return;
     }
 
+    if (!isReferenceConnected(referenceElement) || !popperElement.isConnected) {
+      return;
+    }
+
     const createPopper = options.createPopper || defaultCreatePopper;
     const popperInstance = createPopper(referenceElement, popperElement, popperOptions);