pfSense

If you set "Any" as the Destination port range for a Port Forward TCP or UDP entry, upon saving the new rule you get the following errors:

The following input errors were detected:
- The field Destination port from is required.
- The field Destination port to is required.

If you also do not set the Redirect target port for the same entry, which arguably is expected for a "Any" rule, you get the additional error:

- The field Redirect target IP is required.

This has the very easy workaround of manually setting the port range from 1 to 65535, and the redirect port to 1.

(I'm marking this as a Feature as the "Any" label was probably intended for other protocol choices, but definitely makes sense for TCP and UDP too.)