Examine source code of Stereogum Vocalizer

{
  "description": "Reads the comments out loud using the browser's builtin speech synthesizer",
  "manifest_version": 2,
  "name": "Stereogum Vocalizer",
  "version": "0.0.5",
  "icons": {
    "16": "icons/record_voice_over/1x/baseline_record_voice_over_black_16dp.png",
    "18": "icons/record_voice_over/1x/baseline_record_voice_over_black_18dp.png",
    "32": "icons/record_voice_over/1x/baseline_record_voice_over_black_32dp.png",
    "36": "icons/record_voice_over/1x/baseline_record_voice_over_black_36dp.png"
  },
  "content_scripts": [
    {
      "matches": [
        "https://*.stereogum.com/*"
      ],
      "js": [
        "vocalize.js",
        "audio.js"
      ],
      "css": [
        "vocalize.css"
      ],
      "run_at": "document_end"
    }
  ],
  "web_accessible_resources": [
    "icons/*/1x/*.png"
  ]
}