Examine source code of Grey ancient moon

{
  "theme": {
    "images": {
      "theme_frame": "Grayancientmoon1.jpg"
    },
    "colors": {
      "frame": "#fcfcfc",
      "tab_background_text": "#545151"
    }
  },
  "version": "2.0",
  "name": "Grey ancient moon",
  "manifest_version": 2,
  "description": "Just in black and white, like in the old movies."
}