: Implemented High Efficiency Video Coding for better video compression. Apple Support Community Where to Find the Official Installer
If you need High Sierra only for testing or legacy software, consider using or a cloud-based Mac service instead of an .iso . Macos High Sierra 10.13.6.iso
macOS High Sierra is considered "End of Life" by Apple. It no longer receives security updates, making it vulnerable to modern threats. It should only be used in isolated environments or for specific legacy hardware maintenance. : Implemented High Efficiency Video Coding for better
: If you are already on a Mac, you can often download the official installer via the Mac App Store and then use a Terminal command to create your own ISO. It no longer receives security updates, making it
: Introduced "Intelligent Tracking Prevention" to block advertiser tracking and "Autoplay Blocking" to silence noisy web pages automatically.
: Copying a 5GB file takes milliseconds because the system creates a "clone" rather than physically moving data.