[Engage] Issues with displaying Design Studio messages

Update timeline

1. investigating May 22, 2026, 09:28 AM UTC

   We are currently investigating an issue with displaying Design Studio messages. At this stage, information is limited, further updates will be shared as soon as possible.

2. identified May 22, 2026, 09:50 AM UTC

   We have identified the issue and are preparing a hotfix.

3. identified May 22, 2026, 10:02 AM UTC

   We are currently experiencing issues affecting the display and creation of messages in Design Studio. Sending messages is not impacted.

4. monitoring May 22, 2026, 10:40 AM UTC

   A fix has been implemented and is working. We are monitoring for now.

5. resolved May 22, 2026, 12:45 PM UTC

   The system has been stable since the fix earlier today. Post mortem will be performed and an incident report will be added.

6. postmortem Jun 02, 2026, 09:54 AM UTC

   ### Summary On Friday, May 22, between approximately 11:15 and 12:45 CEST, users experienced issues when opening the Design Studio in Engage to list send-out messages. Message sending was not impacted. Scheduled send-outs, automation send-outs, and message delivery to recipients continued to work as expected. The issue was resolved after deploying a hotfix to the affected frontend services. ### Customer impact Customers using Design Studio in Engage were affected, the classic email editor was not impacted. During the incident, affected users could experience problems with: * Viewing existing send-outs * Working with send-outs * Opening the Design Studio There was no impact on recipients or outbound message delivery. ### Root cause The issue was caused by a recent frontend change related to new functionality in Engage. A component connected to this new functionality resulted in an issue failing to load the send-out list and Design studio. ### Mitigation Internal and external reports about the issue was notified to the Engineering team who started investigating immediately. The affected area was quickly identified, and a hotfix was prepared. The fix was then deployed to the affected frontend services in batches to reduce risk. The fix was verified during the deployment and the incident was resolved at approximately 12:45 CEST. ### Next steps We are reviewing both technical safeguards and release routines to reduce the risk of similar incidents. We apologize for the disruption this caused for affected users and thank you for your patience while we worked on the resolution.