I use Acrobat Reader to digitally sign pdf files by using the certificates stored on a USB drive. After upgrading my Mac OS to 11.3 and update to the Acrobat Reader, it does not provide the option in the attached screen to put in the user pin of the token. After clicking sign, there is an option to save the files and then there is a pop up to enter user pin.
Security digital signatures and esignatures
Just want to add to the above post that entering the user pin does not work. It does not accept the user pin and does not sign the document. There is no problem with the user pin as I am able to use that and separately access the certificate on the USB token.