HADashboard display nothing

Appdaemon version: 2.1.10

I installed the Appdaemon, and launched it. The HADashboard display nothing.
the snap:

this is Hello.dash, I didn’t change anything.

Main arguments, all optional

title: Hello Panel
widget_dimensions: [120, 120]
widget_margins: [5, 5]
columns: 8

label:
widget_type: label
text: Hello World

layout:
- label(2x2)

hassio?

there are still issues with that.
you probably have errors in your log.