How to encrypt a bootable clone in macOS

Make sure your Mac's bootable clone is protected.
    Related:
  • Security
  • Mac
  • FileVault 2
  • MacOS Sierra
Glenn Fleishman’s most recent books include Take Control of iOS & iPadOS Privacy and Security, Second Edition (covering iOS 15/iPadOS 15), Take Control of Your M-Series Mac, and Take Control of Securing Your Mac. In his spare time, he makes Tiny Type Museums. He’s a senior contributor to Macworld, where he writes Mac 911.