diff --git a/packages/react-devtools-shared/src/utils.js b/packages/react-devtools-shared/src/utils.js
index a0ec1038e75dc..8ec60e426bded 100644
--- a/packages/react-devtools-shared/src/utils.js
+++ b/packages/react-devtools-shared/src/utils.js
@@ -401,6 +401,7 @@ export type DataType =
   | 'html_element'
   | 'infinity'
   | 'iterator'
+  | 'opaque_iterator'
   | 'nan'
   | 'null'
   | 'number'
@@ -460,6 +461,8 @@ export function getDataType(data: Object): DataType {
         // If it doesn't error, we know it's an ArrayBuffer,
         // but this seems kind of awkward and expensive.
         return 'array_buffer';
+      } else if (data[Symbol.iterator] === 'data') {
+        return 'opaque_iterator';
       } else if (typeof data[Symbol.iterator] === 'function') {
         return 'iterator';
       } else if (data.constructor && data.constructor.name === 'RegExp') {
@@ -678,6 +681,8 @@ export function formatDataForPreview(
       } else {
         return `${name}(${data.size})`;
       }
+    case 'opaque_iterator':
+      return `${data.constructor.name}(${data.length})`;
     case 'date':
       return data.toString();
     case 'object':