diff --git a/manifest.json b/manifest.json
index 4d204b3..37dc59f 100644
--- a/manifest.json
+++ b/manifest.json
@@ -2,7 +2,7 @@
 
   "manifest_version": 2,
   "name": "Witzig! - Nicht Witzig!",
-  "version": "0.3",
+  "version": "0.4",
 
   "description": "Replaces the thumb up and down in YouTube with a Witzig! and a Nicht Witzig! stamp.",
 
diff --git a/witzig.js b/witzig.js
index 586ecc1..377c504 100644
--- a/witzig.js
+++ b/witzig.js
@@ -20,6 +20,10 @@ function log(msg) {
   console.log("W!NW!: " + msg);
 }
 
+function getURL(path) {
+  return chrome.runtime.getURL(path) || browser.runtime.getURL(path);
+}
+
 /*
 Grafikfunktionen
 */
@@ -50,9 +54,9 @@ function inject() {
   log("Stempelfläche vergrößert.");
   var image_container_object = document.querySelectorAll(image_container_path);
   log("Packe Stempel aus...");
-  inject_image(image_container_object[0], browser.extension.getURL("media/sticker-witzig.png"));
+  inject_image(image_container_object[0], getURL("media/sticker-witzig.png"));
   log("Witzig!");
-  inject_image(image_container_object[1], browser.extension.getURL("media/sticker-nicht-witzig.png"));
+  inject_image(image_container_object[1], getURL("media/sticker-nicht-witzig.png"));
   log("Nicht Witzig!");
 }