add message receiving in the background

scripts/background/link.js

@@ -0,0 +1,12 @@
+/* link.js
+Link the content scripts to the background scripts. 
+*/
+
+class link {
+     constructor () {
+          // Create a listener for events. 
+          chrome.runtime.onMessage.addListener(async (message, sender, sendResponse) => {
+               
+          });
+     }
+}