MSTeams receiver with empty title/text triggers prometheus operator panic

apiVersion: monitoring.coreos.com/v1alpha1
kind: AlertmanagerConfig
metadata:
  name: alertmanager-config
  labels:
    resource: prometheus
spec:
  route:
    groupBy: ["..."]
    groupWait: 1m
    groupInterval: 1m
    repeatInterval: 12h
    receiver: "default_channel"
    routes:
      - matchers:
        - matchType: =
          name: severity
          value: warning
        receiver: teams
receivers:
    - name: "default_channel"
    - name: teams
      msteamsConfigs:
        - webhookUrl:
            name: alertmanager-teams
            key: webhook