Examine source code of Bokeh Lens

{
  "theme": {
    "images": {
      "theme_frame": "neg.jpg"
    },
    "colors": {
      "frame": "#f9faf7",
      "tab_background_text": "#fdfcff"
    }
  },
  "version": "2.0",
  "name": "Bokeh Lens",
  "manifest_version": 2,
  "description": "Bokeh is how lenses render out-of-focus areas. "
}