I finally found the solution! In config.inc.php
configuration file, I changed this line:
$cfg['Servers'][$i]['hide_db'] = '(mysql|information_schema|performance_schema|test|phpmyadmin)';
With:
$cfg['Servers'][$i]['hide_db'] = '^(mysql|information_schema|performance_schema|test|phpmyadmin)$';
Now it works fine!