Examine source code of Toggle Tabs Audio

{
  "author": "igorlogius",
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "commands": {
    "Assign Group 1": {
      "suggested_key": {
        "default": "F1"
      }
    },
    "Toggle Group 1": {
      "suggested_key": {
        "default": "F2"
      }
    },
    "Assign Group 2": {
      "suggested_key": {
        "default": "F3"
      }
    },
    "Toggle Group 2": {
      "suggested_key": {
        "default": "F4"
      }
    },
    "Assign Group 3": {
      "suggested_key": {
        "default": "F5"
      }
    },
    "Toggle Group 3": {
      "suggested_key": {
        "default": "F6"
      }
    },
    "Assign Group 4": {
      "suggested_key": {
        "default": "F7"
      }
    },
    "Toggle Group 4": {
      "suggested_key": {
        "default": "F8"
      }
    }
  },
  "browser_action": {
    "default_title": "Remove Audio Groups"
  },
  "icons": {
    "256": "icon.png"
  },
  "manifest_version": 2,
  "name": "Toggle Tabs Audio",
  "permissions": [
    "notifications",
    "tabs"
  ],
  "version": "1.1.1",
  "browser_specific_settings": {
    "gecko": {
      "id": "{a879cc95-3da6-4f44-b48b-4ab82b731aca}"
    }
  }
}