Examine source code of Connections Yellow

{
  "theme": {
    "images": {
      "theme_frame": "retrodeco_connections_y_h.png"
    },
    "colors": {
      "frame": "#999933",
      "tab_background_text": "#331a00"
    }
  },
  "version": "2.0",
  "name": "Connections Yellow",
  "manifest_version": 2,
  "description": "These images are from \"Retro-Deco\" which is the website that provides free tiling background images. And the auther is Satsuki Aota."
}