Adding an onMessage listener to my background script

Question

In my Chrome Extension, I want the following steps to execute:

1. Upon clicking the extension icon which triggers a popup, a message is sent using chrome.runtime.sendMessage.
2. The message is received by a listener in the background script using chrome.runtime.onMessage.addListener. This triggers a message to be logged to the console

If I add a console.log command outside of the listener, I DO see the message logged in the dev tools.

However, my message inside the listener is not logged, which leads me to believe the message is not being received.

Am I missing something?

Code:

manifest.json

{
    "name": "xxx",
    "version": "1.0.0",
    "description": "xxx",
    "manifest_version": 3,
    "author": "xxx",
    "action":{
        "default_title": "xxx",
        "default_popup": "index.html"
    },
    "permissions": [
        "activeTab",
        "scripting"
    ],
    "background": {
        "service_worker": "background.js"
    }
}

background.js

chrome.runtime.onMessage.addListener(function (request, sender, sendResponse) {
  console.log("listener");
});

script.js

chrome.runtime.sendMessage({message: "xxx"}, function(response) {
  console.log(response)
});