Examine source code of always old redit

{
  "manifest_version": 2,
  "name": "always old redit",
  "description": "This extension will analyze a reddit",
  "version": "1.0",
  "icons": {
    "16": "icon16.png",
    "48": "icon48.png",
    "128": "icon128.png"
  },
  "content_scripts": [
    {
      "matches": [
        "https://www.reddit.com/*"
      ],
      "js": [
        "check.js"
      ]
    }
  ]
}