Thank you for answering.
After further investigation, I found that the rule "let out anything from the firewall host itself" is logged for every packet with the S/SA flags exiting any interface, including packets traversing the firewall. Therefore, in my case, this rule/log line was not the real indicator of the problem.
After understanding this, I enabled logging correctly and fixed the problem. At this point, I suspect that intra-VLAN traffic might also have been working with the previous firmware... but I have no way to investigate that. In any case, the problem is solved now. Thank you for sending me the links explaining the design choices behind the outbound rules; I think I've learned a bit more about pfctl now.
After further investigation, I found that the rule "let out anything from the firewall host itself" is logged for every packet with the S/SA flags exiting any interface, including packets traversing the firewall. Therefore, in my case, this rule/log line was not the real indicator of the problem.
After understanding this, I enabled logging correctly and fixed the problem. At this point, I suspect that intra-VLAN traffic might also have been working with the previous firmware... but I have no way to investigate that. In any case, the problem is solved now. Thank you for sending me the links explaining the design choices behind the outbound rules; I think I've learned a bit more about pfctl now.
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