[HELP] Upscale Error - Unable to get preview to load

[Selur]

Error is:

u n r e c o g n i z e d   t r a n s f e r   c h a r a c t e r i s t i c s   ( 5 / 0 / 0   = >   0 / 0 / 0 ) .   M a y   n e e d   t o   s p e c i f y   a d d i t i o n a l   c o l o r s p a c e   p a r a m e t e r s .

Strange, I expected:

# setting color transfer (709), if it is not set.
if validate.transferIsInvalid(clip):
  clip = core.std.SetFrameProps(clip=clip, _Transfer=1)

which calls:

def transferIsInvalid(clip: vs.VideoNode) -> bool:
  frame = clip.get_frame(0)
  value = frame.props.get('_Transfer', None)
  return value in [None, 0, 2, 3] or value not in vs.TransferCharacteristics.__members__.values()

to fix this.
=> If you can share a short sample of such a file, I can probably fix it.

Cu Selur