Examine source code of Activate End Tab

{
  "manifest_version": 3,
  "name": "__MSG_extensionName__",
  "description": "__MSG_extensionDescription__",
  "version": "1.0.0",
  "icons": {
    "16": "icons/16.png",
    "32": "icons/32.png",
    "48": "icons/48.png",
    "128": "icons/128.png"
  },
  "default_locale": "en",
  "action": {
    "default_title": "__MSG_extensionName__"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "activate-end-tab.app@expression-inc",
      "strict_min_version": "142.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  }
}