Question about TRACKER_ID

[Mike Grau]

Hello folks.

In 20_body_tests.cf (SA 3.3.2) there is this rule:

body TRACKER_ID   /^[a-z0-9]{6,24}[-_a-z0-9]{12,36}[a-z0-9{6,24}\s*\z/is

What is the "\z" in the regex?

This rule matches "000000000000000000000000000000000000". Is that as
intended?

Thanks!
-- Mike