I am sure that Plesk is already working on a fix.
In the meantime, take a look at my instructions to insert custom CSS.
Or use the command line to monitor the logs:
Code:
tail -f /var/www/vhosts/system/domain.com/logs/proxy_access_ssl_log
tail -f /var/www/vhosts/system/domain.com/logs/proxy_error_log
To monitor multiple subscriptions at the same time, use this:
Code:
tail -f /var/www/vhosts/system/*/logs/proxy_access_ssl_log
tail -f /var/www/vhosts/system/*/logs/proxy_error_log