Examine source code of Cookie Killer Plus

{
  "description": "Clear the cookies of the current domain.",
  "manifest_version": 2,
  "name": "Cookie Killer Plus",
  "version": "1.0.1resigned1",
  "author": "Bill Dorn",
  "homepage_url": "https://github.com/billdorn/cookiekiller",
  "icons": {
    "48": "icons/knife48.png",
    "64": "icons/knife64.png",
    "128": "icons/knife128.png"
  },
  "background": {
    "scripts": [
      "background.js",
      "psl_util.js",
      "psl_tree.js"
    ]
  },
  "browser_action": {
    "default_icon": {
      "48": "icons/knife48.png",
      "64": "icons/knife64.png",
      "128": "icons/knife128.png"
    },
    "default_title": "Cookie Killer"
  },
  "permissions": [
    "tabs",
    "<all_urls>",
    "cookies"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{58ffea7c-ed5a-4662-bac8-26244ee295be}"
    }
  }
}