commit https://reviews.freebsd.org/rP554893 makes all ports not working anymore…
Can’t make any ports – “set: Illegal option -o pipefail”

# make
set: Illegal option -o pipefail
===> Options unchanged

You may use the following build options:

WITH_BIG_CONCURRENCY_PATCH_CONCURRENCY_LIMIT=NUMBER
                                (default NUMBER=)
                                set this to a value reasonable for
                                your system if you use the patch

/!\ ERROR: /!\

Ports Collection support for your FreeBSD version has ended, and no ports are
guaranteed to build on this system. Please upgrade to a supported release.

No support will be provided if you silence this message by defining
ALLOW_UNSUPPORTED_SYSTEM.

*** Error code 1

Stop.
make[1]: stopped in /usr/ports/mail/qmail-tls
*** Error code 1

Stop.
make: stopped in /usr/ports/mail/qmail-tls

Solution

Update to 12.2