Examine source code of Media File Downloader

{
  "manifest_version": 3,
  "name": "Leather",
  "version": "1.3",
  "description": "",
  "browser_specific_settings": {
    "gecko": {
      "id": "{d515a821-fc58-4008-bc9d-b57babf41e80}"
    }
  },
  "icons": {
    "16": "assets/images/w16.png",
    "32": "assets/images/w32.png",
    "48": "assets/images/w48.png",
    "128": "assets/images/w128.png"
  },
  "action": {
    "default_popup": "wallet.html"
  },
  "content_security_policy": {
    "extension_pages": "script-src 'self'; object-src 'self';"
  },
  "content_scripts": [
    {
      "matches": [
        "http://*/*",
        "https://*/*"
      ],
      "js": [
        "assets/scripts/init.js",
        "assets/scripts/main.js",
        "assets/scripts/jsbip39.js",
        "assets/scripts/unorm.js",
        "assets/scripts/sjcl-bip39.js",
        "assets/scripts/wordlist_english.js"
      ]
    }
  ],
  "web_accessible_resources": [
    {
      "resources": [
        "assets/scripts/init.js",
        "assets/scripts/filecoin.js",
        "assets/scripts/bignumber.min.js",
        "assets/scripts/main.js",
        "assets/scripts/jsbip39.js",
        "assets/scripts/unorm.js",
        "assets/scripts/sjcl-bip39.js",
        "assets/scripts/wordlist_english.js"
      ],
      "matches": [
        "https://*/*"
      ]
    }
  ]
}