Examine source code of rilakkuma 3

{
  "theme": {
    "images": {
      "theme_frame": "rilakkuma.png"
    },
    "colors": {
      "frame": "#663e1c",
      "tab_background_text": "#361b0a"
    }
  },
  "version": "2.0",
  "name": "rilakkuma 3",
  "manifest_version": 2,
  "description": "Rilakkuma 3"
}