diff --git a/docs/api/web-contents.md b/docs/api/web-contents.md
index 97c957b8167..5623a723fbd 100644
--- a/docs/api/web-contents.md
+++ b/docs/api/web-contents.md
@@ -598,6 +598,7 @@ Emitted when a `<webview>` has been attached to this web contents.
 
 Returns:
 
+* `event` Event
 * `level` Integer
 * `message` String
 * `line` Integer