Been using Preview for years and only the other day did I realise you can redact stuff. It's the gift that keeps on giving.

Right, you'd think for a company that is all about intuitive UI/UX they would invest more in apps that come installed on all of their computers :/

The fact that you can have a wonderful signature stamp, but the only way to get the image into the system is to hold an image up to your webcam is insane to me.

I have a perfect png signature with transparency, but there's no way to import it.

Page deletion: select the page from the sidebar and press the delete key

Page addition: drag a page from another PDF sidebar into the Preview sidebar

Merging: same, but for a whole PDF

Encryption: File > Edit Permissions > Require Password to Open Document

Decryption: If you have the password, then the same flow

Redaction/Markup/Signatures: All from the Markup menu