pfSense

1. Create a new 1:1 NAT rule
2. Choose interface / external subnet IP
3. Select Any for Internal IP
4. Save/Apply

Result:

There were error(s) loading the rules: /tmp/rules.debug:45: syntax error - The line in question reads [45]: binat on vmx0 inet from  to any -> 10.0.5.215

On previous pfSense versions, a "valid" rule would be created as: binat on vmx0 inet from any to any -> 10.0.5.215

If from any is invalid, then the rule should be disabled on upgrade, and input validation should catch it when it gets saved/re-enabled by the user. If it's supposed to be valid to account for a niche case, then the resulting pf rule should be valid.