Examine source code of ICS Viewer

{
  "manifest_version": 3,
  "name": "__MSG_appName__",
  "version": "0.85",
  "description": "__MSG_appDescription__",
  "default_locale": "nl",
  "permissions": [],
  "action": {
    "default_icon": {
      "48": "icons/calendar-icon-48.png"
    },
    "default_title": "ICS Viewer"
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "icons": {
    "96": "icons/calendar-icon-96.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "ics-viewer@unlisted.addons",
      "strict_min_version": "109.0"
    }
  }
}