Examine source code of Mute Twitch Ads

{
  "manifest_version": 2,
  "name": "Mute Twitch Ads",
  "version": "2.0.1",
  "description": "Will automatically mute any Twitch streams if it plays an add.",
  "permissions": [
    "*://www.twitch.tv/*"
  ],
  "content_scripts": [
    {
      "matches": [
        "*://www.twitch.tv/*"
      ],
      "js": [
        "mute_tab.js"
      ]
    }
  ],
  "browser_action": {
    "default_icon": {
      "48": "twitch_ad_mute_icon_48.png"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{46c0a9b9-dd50-4ac0-a88a-16edbe3b7612}"
    }
  }
}