Examine source code of Sky Blue Background

{
  "name": "Sky Blue Background",
  "manifest_version": 2,
  "version": "1.0",
  "theme": {
    "images": {
      "theme_frame": "1000082461.png"
    },
    "colors": {
      "frame": "rgba(229, 230, 232, 1)",
      "tab_background_text": "rgba(0, 0, 0, 1)",
      "toolbar": "rgba(0, 0, 0, 0)",
      "toolbar_field": "rgba(0, 0, 0, 0)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{953c3cd0-c65e-4199-8c88-20f9a8c51f31}"
    }
  }
}