Examine source code of Joker v2

{
  "manifest_version": 2,
  "version": "1.0",
  "name": "Joker hahaha",
  "theme": {
    "images": {
      "additional_backgrounds": [
        "images/0.png"
      ]
    },
    "properties": {
      "additional_backgrounds_alignment": [
        "right top"
      ],
      "additional_backgrounds_tiling": [
        "no-repeat"
      ]
    },
    "colors": {
      "toolbar": "rgb(33, 36, 40)",
      "toolbar_text": "rgb(255, 255, 255)",
      "frame": "rgb(27, 30, 27)",
      "tab_background_text": "rgb(253, 253, 253)",
      "toolbar_field": "rgb(52, 54, 57)",
      "toolbar_field_text": "rgb(248, 250, 255)",
      "tab_line": "rgba(199, 214, 203, 0.33)",
      "popup": "rgb(60, 60, 60)",
      "popup_text": "rgb(255, 255, 255)",
      "button_background_active": "rgb(42, 45, 47)",
      "button_background_hover": "rgb(20, 26, 29)",
      "frame_inactive": "rgb(0, 0, 0)",
      "icons_attention": "rgb(71, 136, 162)",
      "icons": "rgb(213, 217, 210)",
      "ntp_background": "rgb(33, 33, 33)",
      "ntp_text": "rgb(0, 0, 0)",
      "popup_highlight_text": "rgb(0, 0, 0)",
      "tab_loading": "rgb(59, 62, 66)",
      "tab_selected": "rgb(42, 43, 44)"
    }
  }
}