Examine source code of Reddirect

{
  "manifest_version": 2,
  "name": "Reddirect",
  "version": "1.5",
  "description": "Automatically redirects Reddit URLs to Old Reddit.",
  "icons": {
    "48": "icon.png",
    "96": "icon.png"
  },
  "permissions": [
    "tabs",
    "activeTab",
    "storage"
  ],
  "browser_action": {
    "default_icon": "icon.png",
    "default_title": "Reddirect",
    "default_popup": "popup.html"
  },
  "background": {
    "scripts": [
      "constants.js",
      "background.js"
    ]
  },
  "content_scripts": [
    {
      "matches": [
        "*://old.reddit.com/*"
      ],
      "css": [
        "content.css"
      ],
      "run_at": "document_start"
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{c00f38e8-90e6-4d66-904d-34c6fde1a76f}"
    }
  }
}