Spring Cloud Gateway - How To Modify Response Body In Post Filter

Question

So far, I've not seen any solutions that is working for me. I've tried this and this.

Here is my custom filter:

@Component
public class TestFilter implements GlobalFilter, Ordered {

    @Autowired
    private ModifyResponseBodyGatewayFilterFactory modifyFilter;
    
    @Autowired
    private rewriteBody bodyRewrite;
    
    @Override
    public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {

        return chain.filter(exchange).map(ex -> {
            GatewayFilter delegate = modifyFilter.apply(new ModifyResponseBodyGatewayFilterFactory.Config()
                    .setRewriteFunction(byte[].class, byte[].class, bodyRewrite));
            delegate.filter(exchange, chain);

            return ex;
        });
    }

    @Override
    public int getOrder() {
        return -1;
    }
    
    @Component
    public class rewriteBody implements RewriteFunction<byte[], byte[]> {
        
        @Override
        public Publisher<byte[]> apply(ServerWebExchange exchange, byte[] body) {
            byte[] newBody = "New response".getBytes();
            
            return Mono.just(newBody);
        }
    }
}

The ModifyResponseBodyGatewayFilterFactory works if I implement it in a pre-filter, but how do I modify it in the post-filter.