Examine source code of Manilla Folder

{
  "manifest_version": 2,
  "version": "1.0",
  "name": "Manilla Folder",
  "theme": {
    "images": {
      "additional_backgrounds": [
        "images/bg-009-f069b97f439938a011297c84464f0df6.svg"
      ]
    },
    "properties": {
      "additional_backgrounds_alignment": [
        "top"
      ],
      "additional_backgrounds_tiling": [
        "repeat"
      ]
    },
    "colors": {
      "toolbar": "rgb(247, 223, 180)",
      "toolbar_text": "rgb(0, 0, 0)",
      "frame": "rgb(234, 217, 179)",
      "tab_background_text": "rgb(55, 55, 55)",
      "toolbar_field": "rgb(222, 222, 238)",
      "toolbar_field_text": "rgb(0, 0, 0)",
      "tab_line": "rgb(255, 255, 255)",
      "popup": "rgb(255, 255, 255)",
      "popup_text": "rgb(0, 0, 0)",
      "button_background_active": "rgb(255, 255, 255)",
      "button_background_hover": "rgb(222, 191, 129)",
      "frame_inactive": "rgb(255, 255, 255)",
      "icons_attention": "rgb(255, 255, 255)",
      "icons": "rgb(64, 64, 64)",
      "ntp_background": "rgb(234, 217, 179)",
      "ntp_text": "rgb(249, 246, 246)",
      "popup_border": "rgb(0, 0, 0)",
      "popup_highlight_text": "rgb(0, 0, 0)",
      "popup_highlight": "rgb(255, 255, 255)",
      "sidebar_border": "rgb(149, 16, 0)",
      "sidebar_highlight": "rgb(253, 253, 253)",
      "tab_background_separator": "rgb(0, 0, 0)",
      "tab_loading": "rgb(255, 255, 255)",
      "tab_selected": "rgb(247, 223, 180)",
      "tab_text": "rgb(0, 0, 0)",
      "toolbar_bottom_separator": "rgb(0, 0, 0)",
      "toolbar_field_border_focus": "rgb(255, 255, 255)",
      "toolbar_field_border": "rgb(69, 69, 69)",
      "toolbar_field_focus": "rgb(255, 255, 255)",
      "toolbar_field_highlight_text": "rgb(255, 255, 255)",
      "toolbar_field_separator": "rgb(0, 0, 0)",
      "toolbar_top_separator": "rgb(120, 126, 126)",
      "toolbar_vertical_separator": "rgb(0, 0, 0)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{c95d8eeb-598b-4b2c-a819-e6cf45659733}"
    }
  }
}