"We don’t have the thumb drives for that anymore, Eli," Sarah’s voice crackled, tired and strained. "Apple stopped signing the installers for anything that old years ago. If you try to download it from the App Store now, you get an error."

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Introduced in version 10.13.6, this update added multi-room audio support for iTunes, allowing synchronized music playback across multiple speakers. HEVC Support:

He jammed the USB drive into the back of the old Mac Pro. He held down the Option key, the classic chord of the startup sound filling the quiet room. The boot manager appeared. He selected the orange icon representing his USB drive.