button-card: Buttons on Mobile App not displayed, just an error message

Checklist

• I updated the card to the latest version available
• I cleared the cache of my browser

Describe the bug Buttons does not work on mobile app. Everything worked before 2023.4.x of Home Assistant.

Version of the card Version: 3.5.0

To Reproduce This is the configuration I used:

            - entity: input_boolean.skalskydd_alarm_on_natt
              template: standard
              name: Ytterdörr, natt
              type: 'custom:button-card'
              show_state: true
              variables:
                color_seconds: 120
              state:
                - value: 'on'
                  color: 'rgb(255, 255, 0)'
                  color_type: icon
                  icon: "mdi:shield-home"
                - value: 'off'
                  # color: 'rgb(weather-night)'
                  # color_type: icon
                  color: 'rgb(255, 0, 0)'
                  icon: "mdi:shield-home"
              tap_action:
                action: toggle
                confirmation:
                  text: |
                        Vill du sätta PÅ eller stänga AV larm för ytterdörr nattetid?

Screenshots Mobile app:

MacBook

Expected behavior The buttons is not displayed, instead there is an error message beginning with “Null is not an object (evaluating ‘t.config’)” Desktop (please complete the following information):

• Browser Chrome
• Version 111.0.5563.146

Smartphone (please complete the following information):

• Device: iPhone 12
• OS: [e.g. iOS 16.4.1
• Browser Safari
• Version 16

Additional context Verified on Home Assistant v2023.4.0 and v2023.4.1