Examine source code of GreenMonster

{
  "manifest_version": 2,
  "version": "1.0",
  "name": "GreenMonster",
  "theme": {
    "images": {},
    "properties": {},
    "colors": {
      "toolbar": "rgb(26, 81, 12)",
      "toolbar_text": "rgb(255, 255, 255)",
      "frame": "rgb(16, 51, 7)",
      "tab_background_text": "rgb(255, 255, 255)",
      "toolbar_field": "rgb(16, 51, 7)",
      "toolbar_field_text": "rgb(255, 255, 255)",
      "tab_line": "rgb(26, 81, 12)",
      "popup": "rgb(16, 51, 7)",
      "popup_text": "rgb(255, 255, 255)",
      "ntp_text": "rgba(255, 255, 255, 0)",
      "tab_loading": "rgb(26, 81, 12)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{f6f80a9a-9694-4446-8db9-607f9658e535}"
    }
  }
}