Examine source code of Butterfly&Miku

{
  "theme": {
    "images": {
      "theme_frame": "vochead.png"
    },
    "colors": {
      "frame": "#1dcfb1",
      "tab_background_text": "#96f788"
    }
  },
  "version": "2.0",
  "name": "Butterfly&Miku",
  "manifest_version": 2,
  "description": "Vocaloid Miku with butterflies."
}