diff --git a/extension/background.js b/extension/background.js
index 6d9825e..ef26af2 100644
--- a/extension/background.js
+++ b/extension/background.js
@@ -24,7 +24,7 @@ browser.runtime.onMessage.addListener(async (req, sender) => {
 browser.runtime.onMessageExternal.addListener(
   async ({type, params}, sender) => {
     let extensionId = new URL(sender.url).host
-    handleContentScriptMessage({type, params, host: extensionId})
+    return handleContentScriptMessage({type, params, host: extensionId})
   }
 )