Examine source code of Nazuna - Yofukashi no Uta

{
  "manifest_version": 2,
  "version": "1.0",
  "name": "Nazuna OP Frame",
  "theme": {
    "images": {
      "additional_backgrounds": [
        "images/0.png"
      ]
    },
    "properties": {
      "additional_backgrounds_alignment": [
        "right top"
      ],
      "additional_backgrounds_tiling": [
        "no-repeat"
      ]
    },
    "colors": {
      "toolbar": "rgb(23, 33, 41)",
      "toolbar_text": "rgb(200, 200, 200)",
      "frame": "rgb(13, 16, 18)",
      "tab_background_text": "rgb(71, 73, 75)",
      "toolbar_field": "rgb(30, 41, 50)",
      "toolbar_field_text": "rgb(221, 147, 223)",
      "tab_line": "rgb(221, 147, 223)",
      "popup": "rgb(31, 34, 61)",
      "popup_text": "rgb(215, 226, 239)",
      "button_background_active": "rgb(189, 117, 192)",
      "button_background_hover": "rgb(30, 41, 50)",
      "icons": "rgb(140, 72, 144)",
      "ntp_background": "rgb(23, 33, 41)",
      "toolbar_field_border_focus": "rgba(34, 45, 54, 0)",
      "toolbar_field_border": "rgb(27, 34, 41)",
      "tab_loading": "rgb(221, 147, 223)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{0d1be5ad-041f-423d-b450-f8f7dc064ec8}"
    }
  }
}