\defaultfontfeatures[jetbrainsmono-medium]
   {Extension=.otf,
    UprightFont=JetBrainsMono-Medium,
    ItalicFont=JetBrainsMono-MediumItalic,
    BoldFont=JetBrainsMono-ExtraBold,
    BoldItalicFont=JetBrainsMono-ExtraBoldItalic,
    Contextuals=AlternateOff
}