Examine source code of Lyrics for Spotify

{
  "manifest_version": 2,
  "name": "Lyrics for Spotify",
  "description": "This is an unofficial extension that puts back the Spotify Lyrics!",
  "homepage_url": "https://github.com/angeloevangelista/lyrics-for-spotify",
  "version": "1.0.2",
  "icons": {
    "16": "./icons/16.png",
    "48": "./icons/48.png",
    "128": "./icons/128.png"
  },
  "content_scripts": [
    {
      "run_at": "document_end",
      "matches": [
        "https://open.spotify.com/*"
      ],
      "js": [
        "src/lib/popper.min.js",
        "src/lib/tippy-bundle.umd.min.js",
        "src/lib/consts.js",
        "src/lib/observable.js",
        "src/index.js"
      ],
      "css": [
        "src/styles/web-player.css"
      ]
    }
  ],
  "permissions": [
    "*://pega-a-letra-pro-pai.onrender.com/*"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{16a88e46-a7bf-4574-b670-babd0d46cf8d}"
    }
  }
}