1 files changed, 1 insertions, 1 deletions
diff --git a/toolkit/components/extensions/MessageManagerProxy.sys.mjs b/toolkit/components/extensions/MessageManagerProxy.sys.mjs
index 387b5876e1..110a98a05d 100644
--- a/toolkit/components/extensions/MessageManagerProxy.sys.mjs
+++ b/toolkit/components/extensions/MessageManagerProxy.sys.mjs
@@ -51,7 +51,7 @@ export class MessageManagerProxy {
     Services.obs.removeObserver(this, "message-manager-close");
   }
 
-  observe(subject, topic, data) {
+  observe(subject, topic) {
     if (topic === "message-manager-close") {
       if (subject === this.messageManager) {
         this.closed = true;