Examine source code of Three Hearts

{
  "theme": {
    "images": {
      "theme_frame": "3Hearts.jpg"
    },
    "colors": {
      "frame": "#fcf7f7",
      "tab_background_text": "#f7f2f2"
    }
  },
  "version": "2.0",
  "name": "Three  Hearts",
  "manifest_version": 2,
  "description": "Hearts for love or for Valentines"
}