Why Won’t That Help Book Open?
The Help system in macOS is another of those areas which has become sadly neglected. The last time it had a thorough overhaul was back in High Sierra 10.13.4, when it was taken off life support and left hospital walking unaided. With macOS 11 Big Sur and later it has relapsed, and in some cases can’t open an app’s Help book at all. I suspect that this may not be its fault, but the result of a revamp of UTIs, which are used to identify file types.
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If you inspect a Help book, it’s now displayed as a plain folder, implying that it’s no longer recognised as it has been in the past. Not only that, but macOS itself no longer matches the folder name extension of .help as representing a Help book bundle, but gives it a temporary UTI.
