diff --git a/platform_spec/firefox/manifest.json b/platform_spec/firefox/manifest.json
index 90e5b3885..196447129 100644
--- a/platform_spec/firefox/manifest.json
+++ b/platform_spec/firefox/manifest.json
@@ -34,8 +34,7 @@
 		"open_in_tab": true
 	},
 	"background": {
-		"scripts": ["background.js"],
-		"type": "module"
+		"scripts": ["background.js"]
 	},
 	"action": {
     "default_popup": "html/popup.html"