Examine source code of Homely Dark

{
  "manifest_version": 2,
  "version": "1.0",
  "name": "Homely Dark",
  "theme": {
    "images": {
      "additional_backgrounds": [
        "images/bg-000-5672c42860d5b06e1058dc477397f3ef.svg"
      ]
    },
    "properties": {
      "additional_backgrounds_alignment": [
        "top"
      ],
      "additional_backgrounds_tiling": [
        "repeat"
      ]
    },
    "colors": {
      "toolbar": "rgb(72, 68, 65)",
      "toolbar_text": "rgb(235, 218, 124)",
      "frame": "rgb(40, 29, 20)",
      "tab_background_text": "rgb(235, 219, 178)",
      "toolbar_field": "rgb(40, 29, 23)",
      "toolbar_field_text": "rgb(235, 218, 124)",
      "tab_line": "rgb(235, 219, 178)",
      "popup": "rgba(40, 35, 31, 0.8)",
      "popup_text": "rgb(235, 218, 124)",
      "icons_attention": "rgb(255, 117, 0)",
      "sidebar": "rgb(40, 35, 31)",
      "tab_loading": "rgb(235, 219, 178)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{7e93998f-c026-4857-aaa7-2f411e4a7fd9}"
    }
  }
}