Examine source code of clouds dark v2

{
  "manifest_version": 2,
  "version": "1.0",
  "name": "clouds dark v2",
  "theme": {
    "images": {
      "additional_backgrounds": [
        "images/0.png",
        "images/1.png"
      ]
    },
    "properties": {
      "additional_backgrounds_alignment": [
        "center top",
        "center bottom"
      ],
      "additional_backgrounds_tiling": [
        "no-repeat",
        "no-repeat"
      ]
    },
    "colors": {
      "toolbar": "rgb(102, 91, 140)",
      "toolbar_text": "rgb(219, 205, 240)",
      "frame": "rgb(60, 59, 97)",
      "tab_background_text": "rgb(255, 235, 153)",
      "toolbar_field": "rgb(102, 91, 140)",
      "toolbar_field_text": "rgb(219, 205, 240)",
      "tab_line": "rgb(255, 235, 153)",
      "popup": "rgb(102, 91, 140)",
      "popup_text": "rgb(219, 205, 240)",
      "tab_loading": "rgb(255, 235, 153)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{4342d845-dac0-4773-9864-eb8164a78a23}"
    }
  }
}