Examine source code of Change Case

{
  "manifest_version": 2,
  "name": "__MSG_extensionName__",
  "description": "__MSG_extensionDescription__",
  "version": "1.0.1",
  "default_locale": "en",
  "browser_specific_settings": {
    "gecko": {
      "id": "{030218ba-503d-46d3-8777-85020375d507}",
      "strict_min_version": "68.0"
    }
  },
  "icons": {
    "32": "icons/change-case-32.png",
    "48": "icons/change-case-48.png",
    "96": "icons/change-case-96.png"
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "permissions": [
    "contextMenus"
  ]
}