Azure Firewall: Flow Trace Logs and Autoscaling based on number of connections are now generally available

Flow Trace Logs display logs that show additional TCP handshake logs, such as SYN-ACK, FIN, FIN-ACK, RST, and INVALID. This is particularly helpful for identifying packet drops or asymmetric routes. 

Azure Firewall can now autoscale based on the number of connections, in addition to throughput and CPU usage. This provides the benefit of having your firewall scale with more granular information about your traffic information. 

Learn more.

Azure Firewall auto-scaling behavior 

Enable Top flows and Flow trace logs in Azure Firewall