Browser_mod not working with config-template-card?

This does not work - on a HA with the new variety of browser_mod
It pops up the title and nothing else.

Is it the custom card or something else I’ve overlooked?

        tap_action:
          action: call-service
          service: browser_mod.popup
          service_data:
            title: Lights
            card:
              type: custom:config-template-card
              entities:
                - light.wardrobe
                - light.lounge_light
                - light.lounge_corner
                - light.dining

This however with the old variety of browser_mod does work (on an older HA)

            tap_action:
              action: fire-dom-event
              browser_mod:
                command: popup
                title: Lights
                card:
                  type: custom:config-template-card
                  entities:
                    - light.wardrobe
                    - light.lounge_light
                    - light.lounge_corner
                    - light.dining_room

I found this looking for the answer to another question… but I think I can answer yours.

This Pop-up will show nothing but the title if the light entity is off. If it is on, you will see the slider.

Thanks for responding, but the card delivers much more than a light slider, it shows a whole house diagram with lights that can be touched to turn on and off. Works fine with old version.

First what I noticed - this card definition is incomplete since you have not provided a “card” option.
Probably you just omitted this part of your code, so my observation is not relevant.