Examine source code of OldifyReddit

{
  "manifest_version": 2,
  "name": "OldifyReddit",
  "version": "1.0",
  "description": "New Reddit UI sucks, use this to always be directed to https://old.reddit.com/* instead.",
  "icons": {
    "48": "icons/oldify.png"
  },
  "content_scripts": [
    {
      "matches": [
        "*://*.reddit.com/*"
      ],
      "js": [
        "Oldify_Reddit.js"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{893a3c7f-4cb8-4e85-b5a1-a761c5b7159b}"
    }
  }
}