Examine source code of Capture & Print

{
  "name": "Capture & Print",
  "description": "This add-on lets you print a webpage's area easily.",
  "version": "0.2.1",
  "author": "Diego Casorran dcasorran[a]gmail.com",
  "homepage_url": "https://github.com/diegocr",
  "browser_action": {
    "default_icon": {
      "16": "icon-16.png",
      "32": "icon-32.png",
      "64": "icon-64.png"
    }
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "icons": {
    "16": "icon-16.png",
    "32": "icon-32.png",
    "64": "icon-64.png"
  },
  "permissions": [
    "menus",
    "activeTab",
    "<all_urls>",
    "clipboard",
    "notifications",
    "clipboardWrite"
  ],
  "applications": {
    "gecko": {
      "strict_min_version": "57.0",
      "id": "{146f1820-2b0d-49ef-acbf-d85a6986e10c}"
    }
  },
  "manifest_version": 2
}