#!/usr/bin/perl -w
use strict;

no CGI;
use v5.36;
use feature 'class';
# notice that I commented this out
#no warnings "experimental::class";

package Signals;

our $VERSION=1.0;

package Foo;

class Alpha 0.01 {
    field $longname = "alpha!";
}


package main;
#...

##</code><code>##

class is experimental at cgiuser3.pl line 16.
field is experimental at cgiuser3.pl line 17.