Examine source code of Invisible Voice

{
  "manifest_version": 2,
  "version": "9.26.2resigned1",
  "name": "Invisible Voice",
  "description": "This extension boycotts a website",
  "permissions": [
    "tabs",
    "storage",
    "webRequest",
    "https://invisible-voice.com/*",
    "unlimitedStorage"
  ],
  "icons": {
    "16": "icon16.png",
    "24": "icon24.png",
    "48": "icon48.png",
    "96": "icon96.png"
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "InvisibleVoice.js"
      ],
      "run_at": "document_start"
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{15837df6-2801-449a-b17a-496fdc256834}"
    }
  }
}