diff --git a/src/components/Responses/Response.tsx b/src/components/Responses/Response.tsx
index 6d1e1a28..bc6ece8b 100644
--- a/src/components/Responses/Response.tsx
+++ b/src/components/Responses/Response.tsx
@@ -16,7 +16,8 @@ export class ResponseView extends React.Component<{ response: ResponseModel }> {
     const mimes =
       content === undefined ? [] : content.mediaTypes.filter(mime => mime.schema !== undefined);
 
-    const empty = Object.keys(extensions).length === 0 && headers.length === 0 && mimes.length === 0 && !description;
+    const empty = (!extensions || Object.keys(extensions).length === 0) &&
+      headers.length === 0 && mimes.length === 0 && !description;
 
     return (
       <div>
diff --git a/src/services/__tests__/models/Response.test.ts b/src/services/__tests__/models/Response.test.ts
index ebb836c0..7902293c 100644
--- a/src/services/__tests__/models/Response.test.ts
+++ b/src/services/__tests__/models/Response.test.ts
@@ -39,5 +39,12 @@ describe('Models', () => {
       const resp = new ResponseModel({ ...props, code: 'default', defaultAsError: true });
       expect(resp.type).toEqual('error');
     });
+
+    test('should be error if showExtensions is true', () => {
+      const options = new RedocNormalizedOptions({ showExtensions: true });
+      const resp = new ResponseModel(parser, 'default', true, { 'x-example': {a: 1} } as any, options);
+      expect(Object.keys(resp.extensions).length).toEqual(1);
+      expect(resp.extensions['x-example']).toEqual({a: 1});
+    });
   });
 });