Examine source code of Weathered Metal

{
  "theme": {
    "images": {
      "theme_frame": "header.png"
    },
    "colors": {
      "frame": "#e6dfdf",
      "tab_background_text": "#bf3434"
    }
  },
  "version": "2.0",
  "name": "Weathered Metal",
  "manifest_version": 2,
  "description": "A weathered metal wall from a construction site."
}