diff --git a/README.md b/README.md
index 3233caa7..7435b5bb 100644
--- a/README.md
+++ b/README.md
@@ -165,6 +165,7 @@ deepLinking | If set to `true`, enables dynamic deep linking for tags and operat
 requestInterceptor | MUST be a function.  Function to intercept try-it-out requests.  Accepts one argument requestInterceptor(request) and must return the potentially modified request.
 responseInterceptor | MUST be a function.  Function to intercept try-it-out responses.  Accepts one argument responseInterceptor(response) and must return the potentially modified response.
 showMutatedRequest | If set to `true` (the default), uses the mutated request returned from a rquestInterceptor to produce the curl command in the UI, otherwise the request before the requestInterceptor was applied is used.
+showExtensions | Controls the display of vendor extension (`x-`) fields and values for Operations, Parameters, and Schema. The default is `false`.
 
 ### Plugins