chamilo-lms2/main/inc/lib/mpdf/config.php

<?php

$this->fontdata['couriersans-light'] = array(
    'R' => 'CourierSans-Light.ttf'
);

$this->fontdata['couriersans-lightextra'] = array(
    'R' => 'CourierSans-LightExtra.ttf',
);