Comment by nevf1

It's also what was the cause of the Azure Front Doors global outage two weeks ago - https://aka.ms/air/YKYN-BWZ

"A specific sequence of customer configuration changes, performed across two different control plane build versions, resulted in incompatible customer configuration metadata being generated. These customer configuration changes themselves were valid and non-malicious – however they produced metadata that, when deployed to edge site servers, exposed a latent bug in the data plane. This incompatibility triggered a crash during asynchronous processing within the data plane service. This defect escaped detection due to a gap in our pre-production validation, since not all features are validated across different control plane build versions."