SAML warning, null Reference URI or its Transforms

Getting advice
1

I have a client that is configured with SAML.
After upgrading to Keycloak 15.0.2 I get the warn:
WARN org.apache.jcp.xml.dsig.internal.dom.DOMReference:530 - The input bytes to the digest operation are null. This may be due to a problem with the Reference URI or its Transforms. [1]

Should I care about that?

I should add that when checking the SAMLResponse The Reference URI and its Transforms are all filled with a value.

https://issues.apache.org/jira/browse/SANTUARIO-564