allOf not working properly

[konstantinschuette]

I'm using the webstorm plugin: https://plugins.jetbrains.com/plugin/8433-openapi-generator

I got the following .yaml:

openapi: 3.0.3

info:
  title: API
  description: Description
  version: 1.0.0
  contact:
    name: API Support
    url: 'https://test.de'

servers:
  - url: 'https://localhost:1443/dispatch'
    description: 'Test'

paths:
  /protocols/{protocolId}/addendum/{id}:
    get:
      security:
        - bearerAuth: []
      operationId: getProtocolAddendumById
      summary: Get all addenda corresponding to the protocol
      description: |
        Get all addenda corresponding to the protocol
      tags:
        - Protocol
      parameters:
        - $ref: '#/components/parameters/protocolId'
        - name: id
          in: path
          required: true
          schema:
            type: integer
      responses:
        '200':
          description: Addendum
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/AddendumDetail'
        default:
          description: Unexpected error
          content:
            text/plain:
              schema:
                $ref: '#/components/schemas/Error'

components:
  securitySchemes:
    bearerAuth:
      type: http
      scheme: bearer
      bearerFormat: JWT

  parameters:
    id:
      name: id
      in: path
      required: true
      description: The ID of the data set we want to work with
      schema:
        type: integer
        minimum: 1
    protocolId:
      name: protocolId
      in: path
      required: true
      description: The ID of the protocol data set we want to work with
      schema:
        type: integer
        minimum: 1

  schemas:
    Addendum:
      type: object
      properties:
        id:
          type: integer
          format: int32
          nullable: true
        protocolId:
          type: integer
          format: int32
          nullable: false
        userId:
          type: integer
          format: int32
          nullable: false
        timeStamp:
          type: string
          format: date-time
          nullable: false
        text:
          type: string
          nullable: true
      required:
        - protocolId
        - userId
        - timeStamp

    AddendumDetail:
      type: object
      allOf:
        - $ref: '#/components/schemas/Addendum'
        - type: object
      properties:
        missionDate:
          type: string
          format: date
          nullable: true
        protocolNumber:
          type: string
          nullable: false
        missionNumber:
          type: string
          nullable: true
        nidaId:
          type: string
          nullable: true
        lastname:
          type: string
          nullable: true
        firstname:
          type: string
          nullable: true
        username:
          type: string
          nullable: true

    Error:
      type: object
      properties:
        code:
          type: integer
          format: int64
        message:
          type: string
        fields:
          type: string

I'm exporting with the default settings to typescript-angular:
addendum.model.ts

export interface Addendum { 
    protocolId: number;
    userId: number;
    timeStamp: string;
    id?: number | null;
    text?: string | null;
}

addendum-detail.model.ts

import { Addendum } from './addendum.model';

export interface AddendumDetail { 
    protocolId: number;
    userId: number;
    timeStamp: string;
    id?: number | null;
    text?: string | null;
}

It seems like the additional properties of AddendumDetail will be ignored and only the props of allOf will be used.