Examine source code of Soothing Blue

{
  "theme": {
    "images": {
      "theme_frame": "Sea.png"
    },
    "colors": {
      "frame": "#000000",
      "tab_background_text": "#ffffff"
    }
  },
  "version": "2.0",
  "name": "Soothing Blue",
  "manifest_version": 2,
  "description": "This is a modification of \"The baby of Nevermind\" created by Serial Joker. I removed the baby because Bookmark Toolbar and other stuff etc when drawn on a complex graphic makes the browser look cluttered."
}