Examine source code of Restore Blink Tag

{
  "manifest_version": 2,
  "name": "Restore Blink Tag",
  "version": "2.1resigned1",
  "description": "Restores the functionality of the Blink Tag",
  "author": "Kwan",
  "applications": {
    "gecko": {
      "id": "jid0-ZvgJBhuXKBW4hTDaYjt8WRPr54o@jetpack",
      "strict_min_version": "48.0"
    }
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "css": [
        "blink.css"
      ],
      "all_frames": true
    }
  ]
}