diff --git a/platform/firefox/manifest.json b/platform/firefox/manifest.json
index 9f5469693..57cd914ee 100644
--- a/platform/firefox/manifest.json
+++ b/platform/firefox/manifest.json
@@ -83,10 +83,7 @@
   "sidebar_action": {
     "default_title": "__MSG_statsPageName__",
     "default_panel": "logger-ui.html",
-    "default_icon": {
-      "16": "img/ublock.svg",
-      "48": "img/ublock.svg"
-    }
+    "default_icon": "img/ublock.svg"
   },
   "version": "1.9.15.101",
   "web_accessible_resources": [