Salve ho risposto contattando direttamente l'assistenza di MAMP che mi ha così risposto.........

Hi!
Thank you for leaving note.
Please try to switch to older PHP version (like PHP7.2.x)
After latest Windows updates we have detected system issues with some of the Windows system libraries and PHP7.3
It does not affects older Windows 10 machines (like 1809) and older, they work just fine with PHP7.3
Until Microsoft releases patch or maybe we find some other workaround, one of the solutions is for users to switch to PHP7.2 or older PHP version.
Best Regards,
--
For latest news: Follow us on Twitter:
https://twitter.com/mamp_en
To review the status of the request and add additional comments,
follow the link below: http://appsolute.zendesk.com/hc/requests/33958
You can also add a comment by replying to this email.
Regards
MAMP Support Team