HA_Custom_popup_example.yaml

- type: custom:button-card
  entity: media_player.living_room_tv
  icon: mdi:television
  name: Television
  tap_action:
    action: fire-dom-event
    browser_mod:
      command: popup
      hide_header: true
      card: 
        - type: custom:button-card
          label: Stop
          icon: mdi:stop
          tap_action:
            action: call-service
            service: script.living_room_tv_stop
  hold_action:
    action: more-info