Is there a way to clone the polydata in vtk.js?

I need to clone / duplicate the polydata after reading my VTK file (vtkPolyDataReader),

Just after reading the polydata I want to clone it to then apply a different transform to each clone (polyData)

I tried to use shallowCopy() but it doesn’t giving me what I need, the polyData from the first clone is always affected from what I apply to the second clone

I tried to use something like this const polydata2 = {...polydata1} in javascript, it doesn’t work,

So I’m obliged to use vtkPolyDataReader two times to read my polyData (vtkPolyDataReader.setUrl() two times), but I want to only read one time and clone what I read.

Thank you

If the deepCopy does not work you can do.

const clone = vtk(polydata.getState());