Examine source code of Screenshot Helpers

{
  "manifest_version": 2,
  "name": "Screenshot Helper",
  "version": "1.0",
  "description": "Capture and annotate screenshots of the visible area of a webpage.",
  "icons": {
    "48": "icon.png"
  },
  "browser_action": {
    "default_popup": "popup.html",
    "default_icon": "icon.png"
  },
  "permissions": [
    "activeTab",
    "storage"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{d997f7b9-2d28-40b7-a56c-218cdcc06630}"
    }
  }
}