Change default page setup with MMA version 11.2?

Dear all,
Is there a way to change the default page setup (in File>Page Setup) so that I don’t have to change it every time I start Mathematica?

The default is
inches (in)
Page size Letter/ANSI A
Margins UpDown 1.00 in / LetRight 0.75in

And I would like to change the default values to
Millimiters (mm)
Page size A4
Margins UpDown 10.40 mm/ LetRight 10.05mm

Any suggestions welcome!

Many thanks,

Patrick