Examine source code of Mute Domain Addon

{
  "manifest_version": 2,
  "name": "Mute Domain Addon",
  "version": "1.0",
  "description": "Mutes all tabs for a specific domain.",
  "permissions": [
    "tabs",
    "contextMenus",
    "webNavigation"
  ],
  "background": {
    "scripts": [
      "scripts/background.js"
    ]
  },
  "icons": {
    "48": "icons/icon-48.png",
    "96": "icons/icon-96.png"
  },
  "browser_action": {
    "default_title": "Mute Domain",
    "default_icon": {
      "48": "icons/icon-48.png",
      "96": "icons/icon-96.png"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{d5edb975-f69f-4c87-889d-69bbd8e72ebd}"
    }
  }
}