but I got an "Internal Server Error" so I had to restore "fastcgi" in place of "plesk-php73-fpm".
Having a look at /var/log/httpd/error_log file, I noticed a permission error on "/var/log/plesk-php73-fpm" folder, but I do not know if it could be related.
I attempted following this procedure:
https://support.plesk.com/hc/en-us/articles/213367729-How-to-change-the-PHP-version-for-webmail-on-a-Plesk-for-Linux-server
but I got an "Internal Server Error" so I had to restore "fastcgi" in place of "plesk-php73-fpm".
Having a look at /var/log/httpd/error_log file, I noticed a permission error on "/var/log/plesk-php73-fpm" folder, but I do not know if it could be related.