Examine source code of Reddit Longview

{
  "manifest_version": 2,
  "name": "Reddit Longview",
  "version": "1.0.1",
  "description": "Reddit Sidebar Toggle allows you to hide the Reddit sidebar, adjust content width, and center the layout for a cleaner, more personalized browsing experience. Easily save your settings for a more optimized Reddit interface.",
  "permissions": [
    "storage",
    "*://www.reddit.com/*"
  ],
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "browser_action": {
    "default_popup": "popup.html",
    "default_icon": {
      "16": "icons/16.png",
      "48": "icons/48.png",
      "128": "icons/128.png"
    }
  },
  "content_scripts": [
    {
      "matches": [
        "*://www.reddit.com/*"
      ],
      "js": [
        "content.js"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{f73ef3f8-56d9-46fa-8b82-9481d03a79cc}"
    }
  }
}