Examine source code of FB AIO

{
  "manifest_version": 3,
  "name": "FB AIO",
  "description": "__MSG_extDescription__",
  "version": "2.0.1",
  "icons": {
    "16": "assets/icon16.png",
    "32": "assets/icon32.png",
    "48": "assets/icon32.png",
    "128": "assets/icon128.png"
  },
  "homepage_url": "https://fbaio.org/",
  "default_locale": "en",
  "permissions": [
    "idle",
    "storage",
    "cookies",
    "activeTab",
    "scripting",
    "declarativeNetRequest",
    "declarativeNetRequestWithHostAccess",
    "downloads"
  ],
  "optional_permissions": [
    "tabs"
  ],
  "host_permissions": [
    "*://*/*",
    "<all_urls>"
  ],
  "declarative_net_request": {
    "rule_resources": [
      {
        "enabled": true,
        "id": "ruleset_fb_aio",
        "path": "rules.json"
      }
    ]
  },
  "web_accessible_resources": [
    {
      "resources": [
        "scripts/utils/*.js",
        "scripts/content/helper/*.js"
      ],
      "matches": [
        "<all_urls>"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "extension@fbaio.org",
      "strict_min_version": "121.0",
      "data_collection_permissions": {
        "required": [
          "authenticationInfo"
        ],
        "optional": []
      }
    }
  },
  "background": {
    "type": "module",
    "scripts": [
      "background.js"
    ]
  },
  "action": {
    "default_icon": {
      "32": "assets/icon32.png"
    },
    "default_title": "FB AIO",
    "default_popup": "popup.html"
  },
  "content_scripts": [
    {
      "matches": [
        "*://*/*"
      ],
      "all_frames": true,
      "run_at": "document_start",
      "js": [
        "content-scripts/content.js"
      ],
      "world": "ISOLATED"
    },
    {
      "matches": [
        "*://*/*"
      ],
      "run_at": "document_start",
      "js": [
        "content-scripts/external-bridge.js"
      ],
      "world": "ISOLATED"
    },
    {
      "matches": [
        "*://*/*"
      ],
      "all_frames": true,
      "run_at": "document_start",
      "js": [
        "content-scripts/listener.js"
      ],
      "world": "MAIN"
    }
  ]
}