Examine source code of FreshRSS Checker

{
  "manifest_version": 3,
  "default_locale": "en",
  "name": "__MSG_extensionName__",
  "description": "__MSG_extensionDescription__",
  "author": "Andreas Bielawski",
  "version": "3.1.2",
  "icons": {
    "16": "icons/16.png",
    "32": "icons/32.png",
    "48": "icons/48.png",
    "64": "icons/64.png",
    "128": "icons/128.png"
  },
  "background": {
    "scripts": [
      "build/service-worker.js"
    ],
    "service_worker": "build/service-worker.js",
    "type": "module"
  },
  "action": {
    "default_icon": {
      "16": "icons/16.png",
      "32": "icons/32.png",
      "48": "icons/48.png",
      "64": "icons/64.png",
      "128": "icons/128.png"
    }
  },
  "options_ui": {
    "page": "options/options.html"
  },
  "sidebar_action": {
    "default_icon": {
      "16": "icons/16.png",
      "32": "icons/32.png",
      "48": "icons/48.png",
      "64": "icons/64.png",
      "128": "icons/128.png"
    },
    "default_panel": "sidebar/sidebar.html",
    "open_at_install": false
  },
  "permissions": [
    "alarms",
    "contextMenus",
    "storage"
  ],
  "optional_host_permissions": [
    "http://*/*",
    "https://*/*"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "freshrss-checker@addons.mozilla.org",
      "strict_min_version": "128.0"
    }
  }
}