Examine source code of Email Tracker Blocker 12

{
  "manifest_version": 3,
  "name": "Email Tracker Blocker",
  "version": "1.0.0",
  "description": "Blocks email open/read tracking pixels and link trackers in Gmail, Outlook and Yahoo Mail. Free tier covers core blocking; Lifetime Pro unlocks advanced stats, logs and export.",
  "author": "Ceaser Mwangi",
  "homepage_url": "https://github.com/ceasermwangi/email-tracker-blocker",
  "icons": {
    "16": "icons/icon-16.png",
    "32": "icons/icon-32.png",
    "48": "icons/icon-48.png",
    "128": "icons/icon-128.png"
  },
  "background": {
    "scripts": [
      "background.js"
    ],
    "type": "module"
  },
  "action": {
    "default_popup": "popup/popup.html",
    "default_icon": {
      "16": "icons/icon-16.png",
      "32": "icons/icon-32.png"
    },
    "default_title": "Email Tracker Blocker"
  },
  "options_ui": {
    "page": "options/options.html",
    "open_in_tab": true
  },
  "permissions": [
    "storage",
    "webRequest",
    "declarativeNetRequest",
    "declarativeNetRequestFeedback",
    "alarms",
    "notifications"
  ],
  "host_permissions": [
    "*://mail.google.com/*",
    "*://outlook.live.com/*",
    "*://outlook.office.com/*",
    "*://mail.yahoo.com/*",
    "https://backend-6-gilt.vercel.app/*"
  ],
  "declarative_net_request": {
    "rule_resources": [
      {
        "id": "tracker_ruleset",
        "enabled": true,
        "path": "rules/tracker_rules.json"
      }
    ]
  },
  "content_scripts": [
    {
      "matches": [
        "*://mail.google.com/*",
        "*://outlook.live.com/*",
        "*://outlook.office.com/*",
        "*://mail.yahoo.com/*"
      ],
      "js": [
        "content-scripts/tracker-detector.js"
      ],
      "run_at": "document_idle"
    }
  ],
  "content_security_policy": {
    "extension_pages": "script-src 'self'; object-src 'self'"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "email-tracker-blocker@ceasngi.dev",
      "strict_min_version": "140.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ],
        "optional": [
          "personallyIdentifyingInfo"
        ]
      }
    }
  },
  "default_locale": "en"
}