Examine source code of 3Slate

{
  "manifest_version": 2,
  "version": "1.0",
  "name": "Slate",
  "theme": {
    "images": {},
    "properties": {},
    "colors": {
      "toolbar": "rgb(58, 55, 67)",
      "toolbar_text": "rgb(71, 121, 152)",
      "frame": "rgb(58, 55, 67)",
      "tab_background_text": "rgb(255, 255, 255)",
      "toolbar_field": "rgb(255, 255, 255)",
      "toolbar_field_text": "rgb(137, 132, 154)",
      "tab_line": "rgb(137, 132, 154)",
      "popup": "rgb(255, 255, 255)",
      "popup_text": "rgb(71, 121, 152)",
      "tab_loading": "rgb(137, 132, 154)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{b1df61f0-8455-4cf8-a608-6db95f0f4b9c}"
    }
  }
}