Examine source code of Buy It Yourself

{
  "manifest_version": 2,
  "name": "Buy It Yourself",
  "description": "Why more expensive if you can buy it yourself with lower price. No more middleman online",
  "version": "1.2resigned1",
  "browser_action": {
    "default_icon": {
      "19": "icon19.png",
      "38": "icon38.png"
    }
  },
  "icons": {
    "48": "icon48.png",
    "96": "icon96.png"
  },
  "background": {
    "scripts": [
      "bg.js"
    ]
  },
  "permissions": [
    "*://developer.mozilla.org/*",
    "webRequest",
    "activeTab"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{d4c60866-73fe-487a-b5f7-e1d50a639b2b}"
    }
  }
}