Examine source code of Matrix Gray 3 theme

{
  "manifest_version": 2,
  "version": "1.0",
  "name": "Matrix Gray 3 theme",
  "theme": {
    "images": {},
    "properties": {},
    "colors": {
      "toolbar": "rgb(106, 110, 118)",
      "toolbar_text": "rgb(215, 218, 223)",
      "frame": "rgb(68, 71, 79)",
      "tab_background_text": "rgb(234, 235, 243)",
      "toolbar_field": "rgb(48, 48, 51)",
      "toolbar_field_text": "rgb(218, 218, 230)",
      "tab_line": "rgb(232, 218, 220)",
      "popup": "rgb(84, 85, 91)",
      "popup_text": "rgb(236, 237, 243)",
      "tab_loading": "rgb(232, 218, 220)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{342bc3b7-f543-43a6-b758-f4601ccd7f96}"
    }
  }
}