Examine source code of LinkedIn Exact Applicant

{
  "manifest_version": 2,
  "name": "LinkedIn Exact Applicant",
  "version": "1.0",
  "description": "Replaces 'Over 100 applicants' with the exact count, using LinkedIn Premium data. Works only if you have LinkedIn Premium.",
  "icons": {
    "48": "icons/icon48.png",
    "128": "icons/icon128.png"
  },
  "permissions": [
    "storage",
    "activeTab",
    "tabs"
  ],
  "browser_action": {
    "default_icon": "icons/icon48.png",
    "default_title": "Toggle LinkedIn Counts"
  },
  "content_scripts": [
    {
      "matches": [
        "*://www.linkedin.com/jobs/*"
      ],
      "js": [
        "contentScript.js"
      ],
      "run_at": "document_idle"
    }
  ],
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{8eab2efa-df43-4a69-b22a-ae4a9f0b2171}"
    }
  }
}