Sieve - disable redirect

Hi,

I would like to disallow "redirect" in sieve scripts to prevent automatical e-mail forwarding out of organisation.

I'dint find a way in [1], only "sieve_extensions" option and when I try "sieve_extensions = -redirect" I got:

# sievec test.sieve sievec(root): Warning: sieve: ignored unknown extension 'redirect' while configuring available extensions

Is there any way?

Kind regards Milo

[1] https://doc.dovecot.org/configuration_manual/sieve/configuration/