Examine source code of SPOJ Tool

{
  "name": "SPOJ Tool",
  "version": "1.0",
  "description": "Tool to hide comments from the website.",
  "manifest_version": 2,
  "content_scripts": [
    {
      "matches": [
        "https://www.spoj.com/*",
        "http://www.spoj.com/*"
      ],
      "js": [
        "hello.js"
      ]
    }
  ]
}