diff --git a/README.md b/README.md
index 90607e9c..bcf0ab44 100644
--- a/README.md
+++ b/README.md
@@ -112,6 +112,7 @@ ReDoc makes use of the following [vendor extensions](http://swagger.io/specifica
 * [`x-traitTag`](docs/redoc-vendor-extensions.md#x-traitTag) - useful for handling out common things like Pagination, Rate-Limits, etc
 * [`x-code-samples`](docs/redoc-vendor-extensions.md#x-code-samples) - specify operation code samples
 * [`x-nullable`](docs/redoc-vendor-extensions.md#nullable) - mark schema param as a nullable
+* [`x-displayName`](docs/redoc-vendor-extensions.md#x-displayname) - specify human-friendly names for the menu categories
 
 ### `<redoc>` tag attributes
 * `spec-url` - relative or absolute url to your spec file;