@Goofoff , the feature you are looking for is available in AppService named "Log Stream". This is not yet available for Azure Firewall.
There are two more options that should work with this feature request depending on your workflow. If you are looking for application health centric metrics with inflow and outflow live traffic with minimum latency ~1 sec, then we have application insights "Live Metrics".
Else, we have "Azure firewall workbook" which can gain insights into Azure Firewall events, learn about your application and network rules, and see statistics for firewall activities across URLs, ports, and addresses. Azure Firewall Workbook allows you to filter your firewalls and resource groups, and dynamically filter per category with easy to read data sets when investigating an issue in your logs.
If none of the solution works for your scenario then please feel to raise a feature request here in this feedback section. I recommend you to upvote it and other features that are of interest. In general, Azure feature team would check feasibility of a feature request, triage it, prioritize against existing feature backlog, add in roadmap as appropriate and would announce and/or update the related Azure document once a feature request is addressed.
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