The problem was resolved.
Explicitly specifying Firewall: NAT: Outbound resulted in the intended behavior.
For OPNsense 7 does not use NAT at all, I set Firewall: NAT: Outbound to Disable outbound NAT rule generation.
For OPNsense 8, I created manual rules to use NAT to convert addresses for communications to the WAN from IP addresses other than my own.
Explicitly specifying Firewall: NAT: Outbound resulted in the intended behavior.
For OPNsense 7 does not use NAT at all, I set Firewall: NAT: Outbound to Disable outbound NAT rule generation.
For OPNsense 8, I created manual rules to use NAT to convert addresses for communications to the WAN from IP addresses other than my own.
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