Django manifest.json不加载图标

Question

我一直在尝试找出如何从manifest.json中为Django加载图标。

{
  "short_name" : "Ct",
  "name"       : "CTAI",
  "icons"      : [
    {
      "src"    : "img/black.png",
      "type"   : "image/png",
      "sizes"  : "512x512"
    }
  ],
  "start_url"  :"",
  "background_color" : "#ffffff",
  "display"    : "fullscreen",
  "theme_color": "#172435",
  "scope"      : "/",
  "orientation": "potrait"
}

以及settings.py中django的清单设置

PWA_APP_NAME = 'Ct'
PWA_APP_DESCRIPTION = "The dashboard for all you're needs."
PWA_APP_THEME_COLOR = '#172435'
PWA_APP_BACKGROUND_COLOR = '#ffffff'
PWA_APP_DISPLAY = 'fullscreen'
PWA_APP_START_URL = '/'
PWA_APP_ICONS = [
    {
        'src':  '/black.png',
        'sizes': '512x512'
    }
]

但是我收到此错误。

Error while trying to use the following icon from the Manifest: http://127.0.0.1:8000/ (Download error or resource isn't a valid image)

在开发工具的“应用程序”选项卡中，manifest.json似乎已损坏。我给的设置和这里的设置完全不同。 The dev tools showing the manifest.json

我要去哪里错了？

编辑：我正在关注this。