Model not generated for free-form object for Java client

Created by: zslajosfalvi

    SinglePayment:
      type: object
      description: Single payment
      properties:
        endToEndIdentification:
          type: string

    HungarianCreditTransferIG2:
      type: object
      description: Single payment IG2 fields
      properties:
        payerId:
          type: string

    HungarianCreditTransfer:
      type: object
      allOf:
        - $ref: '#/components/schemas/SinglePayment'
        - $ref: '#/components/schemas/HungarianCreditTransferIG2'
		
    PostHungarianCreditTransferRequest:
      description: Hungarian credit transfer request
      allOf:
        - $ref: '#/components/schemas/HungarianCreditTransfer'

paths:
  /payments/hungarian-credit-transfers:
    post:
      tags:
      - payment-initiation-service
      operationId: postHungarianCreditTransferPayments
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/PostHungarianCreditTransferRequest'
      responses:
        '201':
          description: Payment created
        '404':
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/PostPaymentsResponse'

I used Maven OpenAPI codegen 4.0.0 beta2 with config

            <configuration>
              <generateModelTests>false</generateModelTests>
              <generateApiTests>false</generateApiTests>
              <generateSupportingFiles>false</generateSupportingFiles>
              <inputSpec>${project.build.directory}/classes/xs2a-pisp.yaml</inputSpec>
              <validateSpec>false</validateSpec>
              <generatorName>jaxrs-cxf</generatorName>
              <output>${project.build.directory}/generated-sources</output>
              <configOptions>
                <sourceFolder>java</sourceFolder>
                <apiPackage>${api.package}</apiPackage>
                <modelPackage>${model.package}</modelPackage>
                <useGenericResponse>true</useGenericResponse>
                <useBeanValidation>${useBeanValidation}</useBeanValidation>
                <interfaceOnly>true</interfaceOnly>
              </configOptions>
            </configuration>

SinglePayment HungarianCreditTransferIG2 model classes gets generated, but HungarianCreditTransfer not.

I get the following INFO message: [INFO] Model PeriodicHungarianCreditTransfer not generated since it's a free-form object

Maybe this looks like not a bug, but I need the HungarianCreditTransfer class in my code. Is it possible to force generate this class? With previous version (3.3.4) the HungarianCreditTransfer class is generated.