"test transport" button not present in interface

How can I enable this test button, or where do I find it?

[email protected]:/opt/librenms# ./validate.php
====================================
Component | Version
--------- | -------
LibreNMS  | 1.48.1-32-g25954ccda
DB Schema | 2019_01_16_195644_add_vrf_id_and_bgpLocalAs (131)
PHP       | 7.2.15-1+ubuntu18.04.1+deb.sury.org+1
MySQL     | 10.1.38-MariaDB-0ubuntu0.18.04.1
RRDTool   | 1.7.0
SNMP      | NET-SNMP 5.7.3
====================================

[OK]    Composer Version: 1.8.4
[OK]    Dependencies up-to-date.
[OK]    Database connection successful
[OK]    Database schema correct

Thats just the mail configuration.

For transport, you must go to Alerts->Transport and create a new mail transport.

Then, you can test it.

Thank you. All the config was in place. I did not know the orange button was used to test the transport. Solved. Works like charm.