sieve script not modifying header

Marc
Mon, 17 Oct 2022 08:57:55 -0000

From the command line the sieve script is modifying the header like this:

su testuser -s '/bin/bash' -c 'cat test.msg |
/usr/lib64/dovecot/sieve-execute/sieve-test'

However when executing via dovecot, the header stays unchanged

require
["copy","fileinto","vacation","vnd.dovecot.execute","editheader"];
# rule:[testing2]
if not execute :pipe "sieve-test" {
}

Any idea what I am forgetting to configure/allow?