Examine source code of saubereluftmitmaske

{
  "manifest_version": 2,
  "name": "saubereluftmitmaske",
  "version": "1.0.2resigned1",
  "description": "Adds a red border to all webpages matching saubereluftmitmaske.eu.",
  "icons": {
    "48": "icons/border-48.png"
  },
  "content_scripts": [
    {
      "matches": [
        "*://*.saubereluftmitmaske.eu/*"
      ],
      "js": [
        "saubereluftmitmaske.js"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{781d4967-a6e1-48b4-a4f6-f53370634e95}"
    }
  }
}