Examine source code of Transparent Blue Chill

{
  "manifest_version": 2,
  "version": "1.0",
  "name": "Transparent Blue Chill",
  "theme": {
    "images": {
      "additional_backgrounds": [
        "images/0.jpg"
      ]
    },
    "properties": {
      "additional_backgrounds_alignment": [
        "right top"
      ],
      "additional_backgrounds_tiling": [
        "repeat"
      ]
    },
    "colors": {
      "toolbar": "rgba(28, 31, 47, 0)",
      "toolbar_text": "rgb(255, 255, 255)",
      "frame": "rgb(123, 138, 172)",
      "tab_background_text": "rgb(233, 238, 255)",
      "toolbar_field": "rgba(0, 0, 0, 0.38)",
      "toolbar_field_text": "rgb(255, 255, 255)",
      "tab_line": "rgb(206, 240, 249)",
      "popup": "rgb(71, 80, 98)",
      "popup_text": "rgb(255, 255, 255)",
      "tab_loading": "rgb(206, 240, 249)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{1881bb2f-7291-42b2-ac48-d112cea5644a}"
    }
  }
}