Examine source code of Clean Greens

{
  "manifest_version": 2,
  "version": "1.0",
  "name": "Clean Greens",
  "theme": {
    "images": {},
    "properties": {},
    "colors": {
      "toolbar": "rgb(125, 216, 170)",
      "toolbar_text": "rgb(255, 255, 255)",
      "frame": "rgb(89, 181, 141)",
      "tab_background_text": "rgb(255, 255, 255)",
      "toolbar_field": "rgb(79, 222, 90)",
      "toolbar_field_text": "rgb(255, 255, 255)",
      "tab_line": "rgb(248, 112, 140)",
      "popup": "rgb(125, 197, 165)",
      "popup_text": "rgb(249, 249, 255)",
      "tab_loading": "rgb(248, 112, 140)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{3e922b13-e31c-4950-8ad7-2a389d53c630}"
    }
  }
}