Examine source code of Purple Hymn

{
  "manifest_version": 2,
  "version": "1.0",
  "name": "Purple Hymn",
  "theme": {
    "images": {
      "additional_backgrounds": [
        "images/bg-013-06591d4ad28ab7b9ee90f62f81d6b505.svg"
      ]
    },
    "properties": {
      "additional_backgrounds_alignment": [
        "top"
      ],
      "additional_backgrounds_tiling": [
        "repeat"
      ]
    },
    "colors": {
      "toolbar": "rgb(81, 22, 145)",
      "toolbar_text": "rgb(0, 255, 0)",
      "frame": "rgb(25, 10, 60)",
      "tab_background_text": "rgb(59, 174, 59)",
      "toolbar_field": "rgb(49, 11, 75)",
      "toolbar_field_text": "rgb(255, 255, 255)",
      "tab_line": "rgb(0, 0, 255)",
      "popup": "rgb(52, 52, 165)",
      "popup_text": "rgb(0, 0, 0)",
      "tab_loading": "rgb(0, 0, 255)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{9ed726b9-5116-4570-b844-4df357f67c7b}"
    }
  }
}