\defaultfontfeatures[jetbrainsmono-light]
   {Extension=.otf,
    UprightFont=JetBrainsMono-Light,
    ItalicFont=JetBrainsMono-LightItalic,
    BoldFont=JetBrainsMono-SemiBold,
    BoldItalicFont=JetBrainsMono-SemiBoldItalic,
    Contextuals=AlternateOff
}