[NTG-context] autopdf on MacOS?

When running the command: context --autopdf --run myfile.tex I had hoped the pdfviewer Preview on my MacOS system (version Catalina) would open the pdf for viewing. Allthough a new pdf is created, this is not opened. If the pdf is open in Preview already, it is not updated unless switching to the Preview application. It something wrong here? Is it not functional in MacOS? Am I missing some clue? met vriendelijke groet dr. Hans van der Meer