Added seperate portal to put dom elements inside the flow

packages/react/src/components/ViewPortal/index.tsx

@@ -0,0 +1,19 @@
+import type { ReactNode } from 'react';
+import { createPortal } from 'react-dom';
+
+import { useStore } from '../../hooks/useStore';
+import type { ReactFlowState } from '../../types';
+
+const selector = (s: ReactFlowState) => s.domNode?.querySelector('.react-flow__view-portal');
+
+function ViewPortal({ children }: { children: ReactNode }) {
+  const viewPortalDiv = useStore(selector);
+
+  if (!viewPortalDiv) {
+    return null;
+  }
+
+  return createPortal(children, viewPortalDiv);
+}
+
+export default ViewPortal;