Default http client (Client.Default) seems not taking 'spring.cloud.openfeign.httpclient' properties when creating feign client with FeignClientBuilder

[Siegolas]

I'm creating feign clients using method FeignClientBuilder(context). I'm trying to check the effect of "maxConnections" and "maxConnectionsPerRoute" properties from "spring.cloud.openfeign.httpclient" it seems they are not applied. I'm applying the properties:

spring:
    cloud:
        openfeign:
            httpclient:
                max-connections: 1
                max-connections-per-route: 1

I'm using spring-cloud-openfeign version 4.0.3

A sample of how I create the feign client:

private val target = FeignClientBuilder(context)
        .forType(PhoneMaskingServiceFeignClientExtension::class.java, PHONEMASKINGSERVICE)
        .url(phoneMaskingServiceConfig.url)
        .customize {
            it
                .encoder(GsonEncoder())
                .decoder(gsonDecoder)
                .requestInterceptors(RequestInterceptors.create())
                .requestInterceptor(OpenApiInterceptor())
                .requestInterceptor(HeadersInterceptor(headersConfig.getForwardingHeaders()))
                .requestInterceptor(
                    BasicAuthRequestInterceptor(
                        phoneMaskingServiceConfig.api.user,
                        phoneMaskingServiceConfig.api.password
                    )
                )

        }.build()

However when I force the client to be ApacheHttpClient one and I manually apply the mentioned properties it works as expected and when applying load testing the execution produces timeouts

private val target = FeignClientBuilder(context)
        .forType(PhoneMaskingServiceFeignClientExtension::class.java, PHONEMASKINGSERVICE)
        .url(phoneMaskingServiceConfig.url)
        .customize {
            it
                .encoder(GsonEncoder())
                .decoder(gsonDecoder)
                .client(
                    ApacheHttpClient(
                        HttpClientBuilder.create()
                            .setMaxConnPerRoute(1)
                            .setMaxConnTotal(1)
                            .build()
                    )
                )                
                .requestInterceptors(RequestInterceptors.create())
                .requestInterceptor(OpenApiInterceptor())
                .requestInterceptor(HeadersInterceptor(headersConfig.getForwardingHeaders()))
                .requestInterceptor(
                    BasicAuthRequestInterceptor(
                        phoneMaskingServiceConfig.api.user,
                        phoneMaskingServiceConfig.api.password
                    )
                )

        }.build()

So is there anything wrong in my setup? How can I achieve httpclient props max-connections and max-connections-per-route from "spring.cloud.openfeign.httpclient" are properly applied when using FeignClientBuilder? Is FeignClientBuilder applying "spring.cloud.openfeign.httpclient" properties for the default http client?

Thanks in advance