The CRON jobs to be executed are called up each time a page is viewed by a visitor to the site. By default, these jobs are executed in the background without making the user wait. If you want to force the execution of these jobs directly when the page is displayed, you have to define the following constant in your file config/mes_options.php (See the article dedicated to it).
// force the execution, at each page visit, of scheduled routine jobs
define('_DIRECT_CRON_FORCE',true);
This setting allows to restore the operation of CRON jobs in case your site is protected by a couple of htaccess / htpasswd files.
See also the constant _HTML_BG_CRON_FORCE.