FLAIR: import material from GDML, mass fraction vs atomic relative content

Dear colleagues,
I am trying to import a simple geometry from GEANT4 to FLUKA, exporting from GEANT4 to GDML and then importing the GDML in FLAIR.

I’ve seen a possible issue with the import of a material from GDML to FLAIR.
The relevant lines in GDML defying my material are:

 <material name="GeneralMylar" state="solid">
      <T unit="K" value="293.15"/>
      <MEE unit="eV" value="75.9672951304696"/>
      <D unit="g/cm3" value="1.39"/>
      <fraction n="0.624954472136948" ref="Carbon"/>
      <fraction n="0.0420417295384776" ref="Hydrogen"/>
      <fraction n="0.333003798324575" ref="Oxygen"/>

This defines a material, composed by three elements, that are given as their mass fraction in the material itself.
I imported this into FLAIR, and I see the following:

As you see, the three numbers are interpreted as the atomic fractions, rather than the mass fractions. I think that the proper result for the import should be (I manually fixed this):

May I ask your feedback about this?

Thank you @acelenta for the bug report.
Indeed this bug was introduced some time ago, and it will be corrected in the next respin of flair