try to prevent unnecessary firefox rebuidl

pkgs/firefox-history-exporter/manifest.json

@@ -13,5 +13,10 @@
   },
   "action": {
     "default_popup": "popup.html"
+  },
+  "browser_specific_settings": {
+    "gecko": {
+      "id": "firefox-history-exporter@nmasur.com"
+    }
   }
 }