Examine source code of Mask Detector

{
  "manifest_version": 2,
  "name": "Mask Detector",
  "short_name": "mask-detector",
  "version": "0.2.2resigned1",
  "author": "Lukas Winkler",
  "description": "find websites using the mask Typo3 extension",
  "icons": {
    "128": "img/icon.128.png"
  },
  "page_action": {
    "default_icon": {
      "128": "img/icon-disabled.128.png"
    },
    "default_popup": "popup.html"
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "contentscript.js"
      ]
    }
  ],
  "permissions": [
    "storage",
    "http://*/",
    "https://*/",
    "tabs"
  ],
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "applications": {
    "gecko": {
      "id": "{2b6c2a2b-8cdf-4847-b184-b25d58656722}",
      "strict_min_version": "42.0"
    }
  },
  "options_ui": {
    "page": "options.html",
    "chrome_style": true
  }
}