transformHeader option not working with worker:true?

[nippoolg]

I need to make some transformation on header, but can't get this working with transformHeader option? Got exception:
DOMException: Failed to execute 'postMessage' on 'Worker': (header, index) => header could not be cloned.
Is it supposed to work?
Tried simply : transformHeader: (header: string, index: number) => header

[jtorreslesp]

I am also getting this error. Please let us know how to resolve this, thanks.

[rconjaerts]

This is an issue of papaparse, discussed here: mholt/PapaParse#761