Examine source code of 9GAG Scroll Down

{
  "manifest_version": 2,
  "name": "9GAG Scroll Down",
  "version": "1.0",
  "description": "Adds a scroll down option for 9GAG to the last viewed post.",
  "icons": {
    "48": "icons/9gag_scroll_icon.png"
  },
  "permissions": [
    "storage"
  ],
  "content_scripts": [
    {
      "matches": [
        "*://*.9gag.com/*"
      ],
      "js": [
        "9gagScroll.js"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{deb6426c-d2df-46b8-b3ef-939563189524}"
    }
  }
}