Update manifest for Firefox compatibility

manifest.json

@@ -29,5 +29,11 @@
 		"bookmarks",
 		"webRequest",
 		"webRequestBlocking"
-	]
+	],
+
+	"applications": {
+		"gecko": {
+			"id": "pomf-rehost@lesderid.net"
+		}
+	}
 }