Examine source code of Linkedin EndorseAll

{
  "manifest_version": 2,
  "name": "Linkedin EndorseAll",
  "description": "It endorse all the skills with a single click",
  "version": "1.1resigned1",
  "icons": {
    "48": "icons/icon.png"
  },
  "content_scripts": [
    {
      "js": [
        "content.js"
      ],
      "matches": [
        "*://*.linkedin.com/*"
      ]
    }
  ],
  "page_action": {
    "default_icon": "icons/icon.png"
  },
  "background": {
    "scripts": [
      "bg.js"
    ]
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{0ec233f2-065f-47a5-b339-e3c1266a53e8}"
    }
  }
}