Mapster: map to an interface with both readonly and writeable properties?

We've run into an issue mapping a class to an interface using Mapster 7.2.0. Mapping to target interface

public interface ITarget 
{
  int GetOnlyProperty {get;}
  int GetSetProperty {get;set;}
}

with source.Adapt<ITarget>() always results in GetOnlyProperty having the default value 0.

However, if the target interface has all read-only properties, e.g.

public interface IReadonlyTarget 
    {
      int GetOnlyProperty {get;}
      int GetSetProperty {get;}
    }

both GetOnlyProperty and GetSetProperty are set to the right values from the source.

Is this a bug or a feature, and if a feature, how can one make Mapster populate a target interface with both readonly and writeable target properties?