Examine source code of Deezer BPM

{
  "manifest_version": 3,
  "name": "__MSG_extensionName__",
  "version": "0.7.1",
  "default_locale": "en",
  "description": "__MSG_extensionDescription__",
  "icons": {
    "48": "icons/icon48.png",
    "64": "icons/icon64.png",
    "128": "icons/icon128.png"
  },
  "homepage_url": "https://octogene.github.io/deezer-bpm/",
  "background": {
    "service_worker": "background.js",
    "scripts": [
      "background.js"
    ]
  },
  "action": {
    "default_popup": "popup/popup.html",
    "default_title": "Deezer BPM",
    "default_icon": {
      "48": "icons/icon48.png",
      "128": "icons/icon128.png"
    }
  },
  "permissions": [
    "storage"
  ],
  "host_permissions": [
    "https://www.deezer.com/*",
    "https://api.deezer.com/*"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{daa6e7d2-9aaf-4898-89a4-0f7224841a44}",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  },
  "content_scripts": [
    {
      "matches": [
        "https://www.deezer.com/*"
      ],
      "js": [
        "content/constants.js",
        "content/manual-bpm.js",
        "content/utils.js",
        "content/cache.js",
        "content/api.js",
        "content/resolver.js",
        "content/badge.js",
        "content/playlist.js",
        "content/observers.js",
        "content/main.js"
      ],
      "css": [
        "styles.css"
      ],
      "run_at": "document_idle"
    }
  ]
}