Automatic NAT rule generation failure and (RFC 3021) /31 not supported?!?

[Justeco]

I have been running pfSense at home for a while, and was attempting to replicate
my config on an opnsense router I recently installed...

My v4 connecting range to my ISP is a /31.
And I don't know if this is relevant, but it is a /31 that begins with a 0,
so the range is xxx.xxx.130.0/31  with the .1 address on my side and .0 as
gateway.

I noticed that there were no NAT rules being automatically generated (I set up a gateway,
and it appears to be auto-selected as the default).  In attempting to
troubleshoot why that would be, I decided to step through the setup wizard to see if I
had missed something non-obvious.  The Wizard has a drop down for WAN interface
IP address which specifically omits 31!  It goes from /30 to /32.

Just to see what would happen, I selected an incorrect /30 subnet and let the Wizard
complete.  It didn't seem to set up anything I was missing, however the auto-generated NAT
rules were now present.

Are auto NAT rules not generated if you don't use the Wizard?

Were they not generated because of my /31 WAN range?

Is this just an interface bug?

I'm back on my Netgate 2100 for now, but would love to solve this issue.

Thanks in advance for your attention.

[Justeco]

I guess nobody knows the answer to this.
I supposed I should just submit a bug report.

[Justeco]

I have submitted a bug report for part of this.
However, I suspect I am running in to more than one bug here.

https://github.com/opnsense/core/issues/6463