Is it possible to use in JavaScript interface created in Kotlin.js?

Question

I try to reduce my codebase by using a KMM library compiled for Jvm, Android and Javascript.

The simplest code in Kotlin:

@JsExport
actual interface DataTransferObject {

actual val _type: String
    get() = "temp"
}

Produces the following code in Javascript:

interface DataTransferObject {
    readonly _type: string;
    readonly __doNotUseOrImplementIt: {
        readonly "info.cotique.rest.commons.DataTransferObject": unique symbol;
    };
}

What is __doNotUseOrImplementIt? This name says that I am not to use the interface. Why so? Is there a way to make Kotlin stop adding such fields?

UPDATE One more example in Kotlin:

@JsExport
interface IdDTO<I: Comparable<I>>: DataTransferObject {

    var id: I?

}

Produces in JavaScript

interface IdDTO<I extends info.cotique.rest.commons.Comparable<I>> extends info.cotique.rest.commons.DataTransferObject {
    id: Nullable<I>;
    readonly _type: string;
    readonly __doNotUseOrImplementIt: {
        readonly "info.cotique.rest.commons.IdDTO": unique symbol;
    } & info.cotique.rest.commons.DataTransferObject["__doNotUseOrImplementIt"];
}