Examine source code of Black-grill

{
  "theme": {
    "images": {
      "theme_frame": "Header-black-retina.png"
    },
    "colors": {
      "frame": "#595959",
      "tab_background_text": "#ffffff"
    }
  },
  "version": "2.0",
  "name": "Black-grill",
  "manifest_version": 2,
  "description": "Created by Gabry <a href=\"https://outgoing.prod.mozaws.net/v1/2f525ac6f48e8de96ddf28b5e3bd84d7b111273198a0640aa9b99b46bb4ef1b6/http%3A//gabrydesign.jimdo.com/\" rel=\"nofollow\">http://gabrydesign.jimdo.com/</a>"
}