Payload formatter Linter Failure?

[joembedded]

Hello all,

for no reason the payload formatter's Linter creates a single error (everthing is correct and formatter is working perfectly on TTN and ChirpStack):

Also the Linter complains about missing ';' (as not required in JS) and does not unterstand the ? in "variable?.optional_property"

I am using the QuickJS Engine for Dev. and yy Payload formatters are here: https://github.com/joembedded/payload-decoder

Best regards, Jo