Examine source code of Soil colors

{
  "manifest_version": 2,
  "version": "1.0",
  "name": "Soil colors",
  "theme": {
    "images": {
      "additional_backgrounds": [
        "images/bg-000-5672c42860d5b06e1058dc477397f3ef.svg"
      ]
    },
    "properties": {
      "additional_backgrounds_alignment": [
        "top"
      ],
      "additional_backgrounds_tiling": [
        "repeat"
      ]
    },
    "colors": {
      "toolbar": "rgb(168, 100, 48)",
      "toolbar_text": "rgb(229, 197, 83)",
      "frame": "rgb(54, 48, 44)",
      "tab_background_text": "rgb(158, 182, 165)",
      "toolbar_field": "rgb(203, 202, 201)",
      "toolbar_field_text": "rgb(69, 60, 59)",
      "tab_line": "rgb(216, 198, 175)",
      "popup": "rgb(211, 200, 196)",
      "popup_text": "rgb(95, 99, 104)",
      "tab_loading": "rgb(216, 198, 175)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{1a1365cc-12eb-41c0-9364-52bbb093915a}"
    }
  }
}