diff --git a/crates/web-sys/webidls/enabled/nsISupports.webidl b/crates/web-sys/webidls/enabled/nsISupports.webidl
index 7578b9d5..cf6cd8f2 100644
--- a/crates/web-sys/webidls/enabled/nsISupports.webidl
+++ b/crates/web-sys/webidls/enabled/nsISupports.webidl
@@ -1,4 +1,4 @@
 // `nsISupports` is a Gecko thing that can be queried if it implements some
 // interface. We can query anything via `JsCast`, so it is good enough to just
 // call it an Object.
-typedef Object nsISupports;
+typedef object nsISupports;