Why won't all iframe cards go full width?

[Mastiff]

I have a Lovelace setup for a tablet I’m going to use in my boat (in a waterproof bag, with an aluminum frame I’ve made myself). In that tablet setup I have one iframe for SignalK (shows engine and navigation info from NMEA) with this code:

type: vertical-stack
cards:
  - type: iframe
    url: http://192.168.3.1/@signalk/instrumentpanel/
    aspect_ratio: 90%

That gives me this view:

But using the exact same code on another page in the same setup, for J.River Media Center won’t work the same way:

type: vertical-stack
cards:
  - type: iframe
    url: http://192.168.3.1:16000
    aspect_ratio: 90%

The result is this:

So not even close to full screen. Can somebody please tell me why the same code isn’t doing the same thing with two different pages? Screenshots are taken on my PC, and it’s not because the page won’t go bigger. Here’s the same page in Chrome without Home Assistant:

[boheme61]

are you using “Panel-View” in both views ?

[Mastiff]

Thanks for the quick answer and the right answer! I had forgotten to go beyond the normal code edit and to the raw edit from the upper left three dots! Working now.

[Haldi]

Ohhhhh that’s it Thanks!

So you need to edit the Panel Titel with the pen button.

Then you get this setting with the Panel (1 Card)