Examine source code of Copper Vein

{
  "manifest_version": 2,
  "version": "1.0",
  "name": "Copper Vein",
  "theme": {
    "images": {
      "additional_backgrounds": [
        "images/bg-000-5672c42860d5b06e1058dc477397f3ef.svg"
      ]
    },
    "properties": {
      "additional_backgrounds_alignment": [
        "top"
      ],
      "additional_backgrounds_tiling": [
        "repeat"
      ]
    },
    "colors": {
      "toolbar": "rgb(124, 149, 143)",
      "toolbar_text": "rgb(0, 0, 0)",
      "frame": "rgb(55, 70, 68)",
      "tab_background_text": "rgb(202, 202, 202)",
      "toolbar_field": "rgba(229, 237, 226, 0.75)",
      "toolbar_field_text": "rgb(11, 118, 123)",
      "tab_line": "rgb(118, 154, 145)",
      "popup": "rgb(230, 230, 230)",
      "popup_text": "rgb(26, 26, 26)",
      "icons": "rgba(13, 96, 96, 0.8)",
      "toolbar_field_border": "rgb(100, 142, 131)",
      "toolbar_top_separator": "rgb(100, 142, 131)",
      "tab_loading": "rgb(118, 154, 145)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{786be9fa-323f-472b-9608-2bbcbe3ca64c}"
    }
  }
}