Examine source code of Intentional Twitter

{
  "manifest_version": 3,
  "name": "Intentional Twitter",
  "description": "Display each minute spent on twitter.",
  "version": "1.0.2",
  "browser_specific_settings": {
    "gecko": {
      "id": "intentionaltwitter@strangestloop.io",
      "strict_min_version": "42.0"
    }
  },
  "content_scripts": [
    {
      "matches": [
        "https://twitter.com/*",
        "https://x.com/*"
      ],
      "js": [
        "content.js"
      ]
    }
  ],
  "action": {
    "default_icon": {
      "16": "128.png",
      "48": "128.png",
      "128": "128.png"
    }
  },
  "icons": {
    "16": "128.png",
    "48": "128.png",
    "128": "128.png"
  }
}