This is the same issue as https://hibernate.atlassian.net/browse/HHH-11477 and can be reproduced the same way. That issue is marked as fixed in 5.2.9 but can be reproduced in 5.4.3.
A temporary workaround is to provide a custom dialect remapping CLOB to LongVarcharTypeDescriptor but I'd prefer to use the provided dialect.
Any hint about this?
PostgreSql 11 (verified on 9.4 too)
jdbc postgresql driver 42.2.5