Examine source code of Atikin Contrast

{
  "manifest_version": 2,
  "name": "Atikin Contrast",
  "version": "1.0",
  "description": "Check text-background color contrast accessibility.",
  "icons": {
    "48": "icon.png"
  },
  "browser_action": {
    "default_popup": "index.html",
    "default_icon": "icon.png"
  },
  "permissions": [],
  "browser_specific_settings": {
    "gecko": {
      "id": "{97015e01-b859-4840-ba98-87346050cb53}"
    }
  }
}