1 files changed, 1 insertions, 1 deletions
diff --git a/browser/components/shell/content/setDesktopBackground.js b/browser/components/shell/content/setDesktopBackground.js
index 7448a3e076..70ab825354 100644
--- a/browser/components/shell/content/setDesktopBackground.js
+++ b/browser/components/shell/content/setDesktopBackground.js
@@ -234,7 +234,7 @@ if (AppConstants.platform != "macosx") {
     );
   };
 } else {
-  gSetBackground.observe = function (aSubject, aTopic, aData) {
+  gSetBackground.observe = function (aSubject, aTopic) {
     if (aTopic == "shell:desktop-background-changed") {
       document.getElementById("setDesktopBackground").hidden = true;
       document.getElementById("showDesktopPreferences").hidden = false;