Examine source code of Bandcamp Play Pro

{
  "manifest_version": 2,
  "name": "Bandcamp Play",
  "version": "7.0.0",
  "description": "Automation of work with Bandcamp & SoundCloud: tempo adjustment, preserve pitch, playback control by hotkeys, autoplay, etc.",
  "permissions": [
    "tabs",
    "storage",
    "power",
    "https://bandcamp.com/*",
    "https://*.bandcamp.com/*",
    "https://soundcloud.com/*"
  ],
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": false
  },
  "content_scripts": [
    {
      "js": [
        "vendor.js",
        "content.js"
      ],
      "matches": [
        "https://bandcamp.com/*",
        "https://*.bandcamp.com/*",
        "https://soundcloud.com/*"
      ]
    }
  ],
  "browser_action": {
    "default_title": "Bandcamp play settings",
    "default_popup": "./options.html",
    "default_icon": {
      "16": "assets/logo-16.png",
      "32": "assets/logo-32.png",
      "48": "assets/logo-48.png",
      "128": "assets/logo-128.png"
    }
  },
  "icons": {
    "16": "assets/logo-16.png",
    "32": "assets/logo-32.png",
    "48": "assets/logo-48.png",
    "128": "assets/logo-128.png"
  },
  "web_accessible_resources": [
    "assets/close.png",
    "assets/keys/key-0.png",
    "assets/keys/key-9.png",
    "assets/keys/key-B.png",
    "assets/keys/key-down.png",
    "assets/keys/key-L.png",
    "assets/keys/key-left.png",
    "assets/keys/key-N.png",
    "assets/keys/key-O.png",
    "assets/keys/key-P.png",
    "assets/keys/key-right.png",
    "assets/keys/key-up.png",
    "assets/keys/key-V.png",
    "assets/logo-128.png",
    "vendor.js",
    "content.js",
    "options.html"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{80b7c54b-5c2c-4554-b3cf-56936ee9fb2e}"
    }
  }
}