sendMessage from popup to content.js not working in chrome extension

Question

I\'m trying to make a popup interface for a chrome extension. I can\'t seem to send a message from the popup.html/popup.js to the content.js script. Here\'s what I have so far.

Answer 1

The answer from 2105 still works on chrome version 88.0.4324.104. I just tested this. One thing I would update is instead of

alert("started"); in the content.js use console.log("started");

You have your proof (Hit F12, console tab) that it worked which persists for you and you can verify the x number of clicks produces x number of "started" log entries.

Make sure you reload the target page when you "Load Unpacked" each time, that had me stuck for a moment.

my manifest.json looks like this:

{
"name":"Chr Ext",
"description":"blah blah",
"version":"2",
"minimum_chrome_version": "46",
"manifest_version":2,
  "content_scripts": [
  {
    "matches": [
      ""
    ],
    "js": ["content.js"]
  }],
    "permissions": [
        "tabs"
    ],
    "browser_action": {
        "default_popup": "popup.html"
    }
}