Examine source code of SilverBullet

{
  "manifest_version": 2,
  "version": "1.2",
  "name": "Newspaper",
  "theme": {
    "images": {
      "additional_backgrounds": [
        "images/bg-000-5672c42860d5b06e1058dc477397f3ef.svg"
      ]
    },
    "properties": {
      "additional_backgrounds_alignment": [
        "top"
      ],
      "additional_backgrounds_tiling": [
        "repeat"
      ]
    },
    "colors": {
      "toolbar": "rgb(33, 33, 33)",
      "toolbar_text": "rgb(210, 210, 210)",
      "frame": "rgb(57, 57, 57)",
      "tab_background_text": "rgb(162, 162, 162)",
      "toolbar_field": "rgb(34, 34, 34)",
      "toolbar_field_text": "rgb(173, 173, 173)",
      "tab_line": "rgba(255, 255, 255, 0)",
      "popup": "rgb(85, 85, 85)",
      "popup_text": "rgb(242, 242, 242)",
      "ntp_background": "rgb(57, 57, 57)",
      "popup_border": "rgb(41, 41, 41)",
      "tab_selected": "rgb(153, 153, 153)",
      "tab_text": "rgb(0, 0, 0)",
      "toolbar_top_separator": "rgb(14, 14, 14)",
      "tab_loading": "rgba(255, 255, 255, 0)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{4e330b87-dd25-4787-889d-74fd610ec14a}"
    }
  }
}