Examine source code of Smoke Inverted

{
  "theme": {
    "images": {
      "theme_frame": "header"
    },
    "colors": {
      "frame": "#c4c4c4",
      "tab_background_text": "#4f4f4f"
    }
  },
  "version": "2.0",
  "name": "Smoke Inverted",
  "manifest_version": 2,
  "description": "Smoke photograph, colored and inverted."
}