Examine source code of Em3r4ld

{
  "manifest_version": 2,
  "version": "1.0",
  "name": "Emerald",
  "theme": {
    "images": {
      "additional_backgrounds": [
        "images/bg-013-06591d4ad28ab7b9ee90f62f81d6b505.svg"
      ]
    },
    "properties": {
      "additional_backgrounds_alignment": [
        "top"
      ],
      "additional_backgrounds_tiling": [
        "repeat"
      ]
    },
    "colors": {
      "toolbar": "rgba(16, 42, 42, 0.8)",
      "toolbar_text": "rgba(25, 162, 200, 0.95)",
      "frame": "rgb(17, 47, 57)",
      "tab_background_text": "rgb(59, 119, 125)",
      "toolbar_field": "rgba(33, 49, 58, 0.2)",
      "toolbar_field_text": "rgb(131, 191, 251)",
      "tab_line": "rgb(28, 166, 176)",
      "popup": "rgb(22, 54, 75)",
      "popup_text": "rgb(48, 169, 183)",
      "tab_loading": "rgb(28, 166, 176)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{1511ecc7-8306-42bf-a4d4-ea15b28482ac}"
    }
  }
}