Examine source code of Reddit Fix

{
  "manifest_version": 2,
  "name": "Reddit Fix",
  "version": "0.3",
  "description": "Hides previously voted on posts from front page and disables voting on archived reddit posts.",
  "icons": {},
  "applications": {
    "gecko": {
      "id": "acas@mozilla.org"
    }
  },
  "content_scripts": [
    {
      "matches": [
        "*://*.reddit.com/*"
      ],
      "js": [
        "jquery-2.2.3.min.js",
        "redditFix.js"
      ]
    }
  ]
}