RhinoCommon BrepFace accurate BoundingBox Issue

Hi,
if I split any brep and join it back togethor, I will get the correct bounding box of each face in the Rhino GUI by selecting the indivual face and using the BoundingBox command. In RhinoCommon this is not the case. For each face I get the bounding box of the original untrimmed surface. I only get accurate face bounding boxes, if I first shrink all faces of the brep. Is this behaviour in RhinoCommon intended or an issue? Usually, I do not check, if all surfaces are shrunk in my model.

See the simple cpython script below that demonstrates this issue:

import Rhino
import scriptcontext as sc
import rhinoscriptsyntax as rs

def main():

    shrink_faces = True
    #shrink_faces = False

    # Create a rectangle
    split_plane_origin = Rhino.Geometry.Point3d(0, 0, 0)
    split_plane_normal = Rhino.Geometry.Vector3d(0, 1, 0)
    split_plane = Rhino.Geometry.Plane(split_plane_origin, split_plane_normal)

    brep_rectangle = Rhino.Geometry.PlaneSurface(split_plane, Rhino.Geometry.Interval(0, 10), Rhino.Geometry.Interval(0, 100)).ToBrep()
    #sc.doc.Objects.AddBrep(brep_rectangle)

    # Create a split plane at the specified location
    split_plane_origin = Rhino.Geometry.Point3d(50, 0, 5)
    split_plane_normal = Rhino.Geometry.Vector3d(1, 0, 0)
    split_plane = Rhino.Geometry.Plane(split_plane_origin, split_plane_normal)

    split_brep = Rhino.Geometry.PlaneSurface(split_plane, Rhino.Geometry.Interval(-10, 10), Rhino.Geometry.Interval(-10, 10)).ToBrep()
    #sc.doc.Objects.AddBrep(split_surface)

    new_breps = brep_rectangle.Split(split_brep, sc.doc.ModelAbsoluteTolerance)
    
    new_brep = Rhino.Geometry.Brep.JoinBreps(new_breps, sc.doc.ModelAbsoluteTolerance)[0]

    sc.doc.Objects.AddBrep(new_brep)

    if shrink_faces:
        new_brep.Faces.ShrinkFaces()

    for i, face in enumerate(new_brep.Faces):
        print(f'face = {i}, bbox = {face.GetBoundingBox(True)}')

    return


if __name__ == "__main__":
    main()

Using shrink_surfaces=False will print the following:

face = 0, bbox = 0,0,0 - 100,0,10
face = 1, bbox = 0,0,0 - 100,0,10

Using shrink_surfaces=True will print the correct bounding box as follows:

face = 0, bbox = 49.999999999999986,0,0 - 100,0,10
face = 1, bbox = 0,0,0 - 50,0,10

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