Error while serializing Configuration

Hi,
We are upgrading from Spring boot 2.3.12 and Vaadin 14.8.16 to Spring boot 2.7.6 and Vaadin 14.9.2.

Currently I’m facing an exception in the 2.7.6 branch which I am not getting on the current setup.

Is this something you’ve seen before?
exception.txt (19.8 KB)