Examine source code of QuietTwitchAds

{
  "manifest_version": 2,
  "name": "QuietTwitchAds",
  "version": "0.1",
  "description": "Turns the video volume down while Twitch ads are playing.",
  "homepage_url": "https://github.com/swpease/QuietTwitchAds",
  "icons": {
    "48": "icons/icon-48.png",
    "96": "icons/icon-48@2x.png"
  },
  "content_scripts": [
    {
      "matches": [
        "*://*.twitch.tv/*"
      ],
      "js": [
        "content_scripts/content_script.js"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{318f500f-c194-4027-90fb-dba0142185b8}"
    }
  }
}