How to change max header size when logout from Keycloak?

Question

I am using Keycloak for authenticating on my spring boot 3 app. When making a request to logout, I get 431 Request Header Fields Too Large. This is not happening with normal users, just the dev users, which carry 260 Roles. I tried server.max-http-request-header-size=20KB server.tomcat.max-http-response-header-size=20KB, but they don't solve the problem. It throws the exception at this line: ResponseEntity logoutResponse = restTemplate.getForEntity(builder.toUriString(), String.class);

@Component
public class KeycloakLogoutHandler implements LogoutHandler {

    private final RestTemplate restTemplate;

    @Autowired
    public KeycloakLogoutHandler(RestTemplateBuilder builder) {
        this.restTemplate = builder.build();
    }

    @Override
    public void logout(HttpServletRequest request, HttpServletResponse response, Authentication auth) {
        logoutFromKeycloak((OidcUser) auth.getPrincipal());
    }

    private void logoutFromKeycloak(OidcUser user) {
        String endSessionEndpoint = user.getIssuer() + "/protocol/openid-connect/logout";
        UriComponentsBuilder builder = UriComponentsBuilder
                .fromUriString(endSessionEndpoint)
                .queryParam("id_token_hint", user.getIdToken().getTokenValue());

        **ResponseEntity<String> logoutResponse = restTemplate.getForEntity(builder.toUriString(), String.class);**
        if (logoutResponse.getStatusCode().is2xxSuccessful()) {
            log.info("Successfully logged out from Keycloak");
        } else {
            log.error("Could not propagate logout to Keycloak");
        }
    }

}