Examine source code of Opal gradient

{
  "name": "Opal gradient",
  "manifest_version": 2,
  "version": "3.0",
  "theme": {
    "images": {
      "theme_frame": "header.png"
    },
    "colors": {
      "frame": "#6cf3fa",
      "tab_background_text": "#00124f",
      "tab_line": "rgba(255, 255, 255, 1)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{e9bb2b92-df7d-46bf-9138-4afb1f6efc53}"
    }
  }
}