Examine source code of aaa

{
  "manifest_version": 2,
  "name": "Screenshot Cropper",
  "version": "1.12",
  "description": "Capture and crop screenshots in Firefox",
  "icons": {
    "48": "48.png"
  },
  "permissions": [
    "activeTab"
  ],
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "browser_action": {
    "default_title": "Capture and crop screenshot",
    "default_icon": "48.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{1882a217-c198-40ab-b9fe-367d62576804}"
    }
  }
}