To add a digital signature (Mac / Windows) to a PDF, you need to obtain a digital certificate. The certificate is actually the authentication of the user's public key issued by the certificate authority (CA).
PDF Reader Pro currently supports PFX and P12 certificates, which are two common digital certificate file formats. They are essentially the same, with slightly different file extensions and uses. PFX certificates are usually used in Windows environments, while P12 certificates are usually used in non-Windows environments.
Regardless of which format of the certificate is used, it is necessary to ensure the security of the private key and follow relevant security best practices to protect the integrity and confidentiality of the certificate.
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