@FrostedKiwi: Yes, I mean pages. And the device which shows “null:” was a MQTT Sensor. I now set an acronym on all devices where it was not set. So the “problem” is solved for me.
The auto scaling itself works, but the picture is not updating (it was the same before the update I thing, but I don’t care about it, because the pictures where not useful until now . It still shows the picture from 20.02.2017 22:06 like in my post. On the web UI of Pimatic it is updating every 3 seconds. When I change the config to force a recreation of the iFrame device, I can see that your app is reloading the picture, but it always comes back with the old picture. The source for the pictures is the cgi snapshot path of my cameras.
Btw (autoscaling) I don’t know if it was a hard job to implement the autoscaling into the app, but are you able to implement his as well in the iFrame plugin of pimatic?