Examine source code of Theme Toggler

{
  "browser_action": {
    "default_title": "Theme toggler",
    "default_popup": "toggle.html",
    "browser_style": true,
    "default_icon": {
      "48": "border-48.png"
    }
  },
  "version": "1.1resigned1",
  "description": "Toggler for switching the themes in Firefox.",
  "manifest_version": 2,
  "name": "Theme Toggler",
  "permissions": [
    "management"
  ],
  "icons": {
    "48": "border-48.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{9072080f-7321-4db1-badd-053f0c40765e}"
    }
  }
}