Examine source code of metal.de v01

{
  "theme": {
    "images": {
      "theme_frame": "persona_metal.de_oben.jpg"
    },
    "colors": {
      "frame": "#cccccc",
      "tab_background_text": "#d75f15"
    }
  },
  "version": "2.0",
  "name": "metal.de v01",
  "manifest_version": 2,
  "description": "Persona for <a href=\"https://outgoing.prod.mozaws.net/v1/d7d633605542da505a564e69030509b481fa3ccde9f83157d4011970c8f8e85b/http%3A//metal.de\" rel=\"nofollow\">metal.de</a>"
}