Examine source code of blue and grey bubbles

{
  "theme": {
    "images": {
      "theme_frame": "persona-header.png"
    },
    "colors": {
      "frame": "#c0c0c0",
      "tab_background_text": "#2a4abf"
    }
  },
  "version": "2.0",
  "name": "blue and grey bubbles",
  "manifest_version": 2,
  "description": "blue/grey bubbles"
}