Examine source code of Udemy seeks

{
  "manifest_version": 2,
  "name": "Udemy seeks",
  "version": "1.0.11",
  "description": "Add a seek to next caption, time bookmark and other time-seek related feature to Udemy course page.",
  "homepage_url": "https://github.com/huybn5776/udemy-seeks",
  "icons": {
    "32": "icons/udemy-seek-32.png",
    "64": "icons/udemy-seek-64.png",
    "128": "icons/udemy-seek-128.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "@udemy-seeks"
    }
  },
  "browser_action": {
    "default_icon": {
      "32": "icons/udemy-seek-32.png"
    },
    "default_title": "Udemy seeks",
    "default_popup": "popup.html"
  },
  "options_ui": {
    "page": "options-page.html"
  },
  "content_scripts": [
    {
      "matches": [
        "*://*.udemy.com/course/*"
      ],
      "js": [
        "build/content-script.js"
      ],
      "css": [
        "content-script.css"
      ]
    }
  ],
  "permissions": [
    "storage",
    "*://*.udemycdn.com/*"
  ]
}