Examine source code of Emby Remote Play

{
  "manifest_version": 2,
  "name": "Emby Remote Play",
  "version": "1.1.0",
  "description": "Play media on your Emby server directly from Trakt, IMDB, TMDB, or MDBList pages. Browse a movie or show, click Play, and it starts on your Emby device.",
  "author": "Rob",
  "homepage_url": "https://github.com/robemby/emby-remote-play",
  "browser_specific_settings": {
    "gecko": {
      "id": "emby-remote-play@robemby",
      "strict_min_version": "109.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  },
  "icons": {
    "48": "icons/icon-48.png",
    "96": "icons/icon-96.png",
    "128": "icons/icon-128.png"
  },
  "permissions": [
    "storage",
    "activeTab"
  ],
  "content_scripts": [
    {
      "matches": [
        "*://*.trakt.tv/movies/*",
        "*://*.trakt.tv/shows/*",
        "*://app.trakt.tv/movies/*",
        "*://app.trakt.tv/shows/*"
      ],
      "js": [
        "content/shared.js",
        "content/trakt.js"
      ],
      "css": [
        "styles/button.css"
      ],
      "run_at": "document_idle"
    },
    {
      "matches": [
        "*://*.imdb.com/title/*"
      ],
      "js": [
        "content/shared.js",
        "content/imdb.js"
      ],
      "css": [
        "styles/button.css"
      ],
      "run_at": "document_idle"
    },
    {
      "matches": [
        "*://*.themoviedb.org/movie/*",
        "*://*.themoviedb.org/tv/*"
      ],
      "js": [
        "content/shared.js",
        "content/tmdb.js"
      ],
      "css": [
        "styles/button.css"
      ],
      "run_at": "document_idle"
    },
    {
      "matches": [
        "*://*.mdblist.com/movie/*",
        "*://*.mdblist.com/show/*",
        "*://mdblist.com/movie/*",
        "*://mdblist.com/show/*"
      ],
      "js": [
        "content/shared.js",
        "content/mdblist.js"
      ],
      "css": [
        "styles/button.css"
      ],
      "run_at": "document_idle"
    }
  ],
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": false
  },
  "options_ui": {
    "page": "options.html",
    "open_in_tab": true
  },
  "browser_action": {
    "default_icon": {
      "48": "icons/icon-48.png"
    },
    "default_title": "Emby Remote Play",
    "default_popup": "popup.html"
  }
}