Examine source code of Sonos Subs

{
  "manifest_version": 2,
  "name": "Sonos Subs",
  "version": "1.0.7",
  "description": "Enhances the Sonos Web App by displaying song lyrics and more helpful features.",
  "author": "Jeram.ai",
  "icons": {
    "16": "icons/icon16.png",
    "48": "icons/icon48.png",
    "128": "icons/icon128.png"
  },
  "permissions": [
    "notifications",
    "storage",
    "tabs",
    "https://lrclib.net/*"
  ],
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": false
  },
  "content_scripts": [
    {
      "matches": [
        "https://play.sonos.com/*"
      ],
      "js": [
        "content.js"
      ]
    }
  ],
  "web_accessible_resources": [
    "patch.js",
    "10-seconds-of-silence.mp3",
    "icons/icon.png"
  ],
  "browser_action": {
    "default_popup": "popup.html",
    "default_icon": {
      "16": "icons/icon16.png",
      "48": "icons/icon48.png",
      "128": "icons/icon128.png"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "sonos-subs@jeram.ai"
    }
  }
}