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PDF Problems Continue in 10.12.4, but Primarily Affect Developers

Numerous readers have asked me if last week’s macOS 10.12.4 update resolved more of the PDF problems we outlined in “Sierra PDF Problems Get Worse in 10.12.2” (2 January 2017). The previous 10.12.3 update addressed the most serious bug, which caused a PDF edited in Preview to lose its OCR text layer (see “Apple Releases macOS Sierra 10.12.3, iOS 10.2.1, tvOS 10.1.1, and watchOS 3.1.1,” 23 January 2017).

Last week, I polled the developers who had commented on the topic for my first article. The consensus was that Apple’s rewritten-for-Sierra PDFKit framework continues to improve, while simultaneously introducing new bugs.

Christian Grunenberg of DEVONtechnologies said, “Since January I have added several new workarounds and improved old workarounds. The 10.12.4 release makes only one workaround obsolete and introduces a new bug.”

He followed that up a few days later by saying, “In the last 24 hours I received various bug reports related to 10.12.4. In one case a PDF document freezes both DEVONthink and Preview; in another case pages are rendered white (in DEVONthink but also sometimes in Preview and both DEVONthink’s and Preview’s sidebar aren’t rendered at all); and in the last case PDF documents are rendered fuzzy.”

Michael Tsai of C-Command Software initially outlined four bugs that Apple fixed in 10.12.4 and four that remain open, and a day later said that one of his customers had reported another crash that’s new in 10.12.4.

The story for users is somewhat better because developers are either working around the bugs they find or quietly removing functionality until PDFKit works correctly. Michael Tsai also said that there’s a middle ground of display and scrolling glitches that can’t be worked around or avoided.

Nonetheless, users continue to have problems, particularly with large or encrypted PDFs in Preview and other apps that rely on PDFKit for their PDF-related functionality. Nothing seems to be as severe as the OCR text layer deletion bug that 10.12.3 fixed, but if you experience trouble with Preview, try a different app.

For merely viewing a PDF, use the free Adobe Acrobat Reader DC. If you need to manipulate a PDF, turn to Smile’s $74.95 PDFpen, which doesn’t use PDFKit and is thus immune from these issues. Similarly unaffected is Adobe Acrobat DC, which requires a subscription that costs either $24.99 per month if billed monthly or $14.99 per month billed annually (that’s $179.88 per year). Acrobat DC is also included in the full $49.99 per month Creative Cloud subscription.

To answer those who have asked if they can now upgrade to Sierra, I’d have to say that if you rely heavily on apps built on top of PDFKit for viewing and manipulating non-trivial PDFs, it’s probably worth continuing to hold off. If you mostly just read PDFs in Preview, you likely won’t hit any stumbling blocks unless you work with large or encrypted PDFs.


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Comments about PDF Problems Continue in 10.12.4, but Primarily Affect Developers
(Comments are closed.)

I am running 10.12.4 and received a 16 page PDF from my car insurance company. On page 16 are the cards that I print out to provide proof of coverage and keep in the glove box.. These show up basically as a black page or a page that you are looking through a filter and does not print correctly. I tried Acrobat Reader DC and was able to print them.
B. Jefferson Le Blanc  2017-04-04 08:04
This is reminiscent of the networking issues that were introduced in OS X 10.10 Yosemite, which also involved new technology developed by Apple. Whether this is a pattern, and what the pattern reveals about Apple's development expertise is, I'm sure, a matter of opinion. I think it's safe to say, though, that neither of these developments is a positive for the company. In the case of Yosemite, Apple was eventually obliged to revert to the old networking technologies that had been working perfectly well in OS X for years, while Yosemite never did develop into a reliable version of OS X. Nor were the problems with the new networking tech ever resolved so that it might be reintroduced.

It's anybody's guess whether Apple will scrap this new version of PDFKit. If you're waiting for them to fix the bugs therein, I don't recommend holding your breath. Their track record with this sort of thing is hardly encouraging. In the meantime, spending $75 for software to work around Apple's mistakes seems to me to be a less than optimal solution, however necessary in some cases. OS X 10.11 El Capitan is a stable and supported version of OS X. If you rely on PDFs in your workflow even occasionally Sierra seems like a risky gamble.

Which raises serious questions about the pending changes to the Apple file system, which have the potential to bring about problems on an unprecedented scale. If they mess this up they will stop macOS development cold and turn the whole platform into a pathetic joke. There's nothing more fundamental and essential to any OS than the file system. The longer they wait to introduce APFS the better in my opinion. They cannot spend too much time proofing their work. Apple seems to have forgotten, if they ever knew, the carpenter's maxim, measure twice, cut once. These days they don't even seem to be measuring once. That's not to say the macOS file system isn't in need of an overhaul. The issue is whether Apple is competent to implement such an overhaul. This latest boondoggle with PDFKit isn't a good sign.

My gloom and doom may seem excessive; no one would be more pleased than I if Apple stopped this self-destructive cycle of behavior and gave me reason to change my toon. I don't know about you, but I'm not encouraged by this latest failure in Apple's quality control procedures. Clearly they just won't learn from their mistakes. Which means they will continue to make more of them—and we will continue to pay the price for their neglect of the fundamentals of good business.
barefootguru  An apple icon for a TidBITS Contributor 2017-04-04 17:08
'The longer they wait to introduce APFS': Apple's busy converting some billions of iPhones & iPads, Watches and TVs to APFS as they're upgraded to iOS 10.3, tvOS 10.2, and watchOS 3.2.
Andrew Hazlett  2017-05-21 10:01
I thought my pdfs were being glitchy because maybe there was something wrong with my graphics card. It's a relief and a frustration to realize it is Sierra. There are certain sets of users who *live* in pdfs, e.g., lawyers, academics, journalists, and more. I find it very depressing that Apple left these issues unattended or half-addressed. There are certain basics a user has got to be able to count on, but I guess wielders of pdfs make up a tiny micropercentage of Apple's customers at this point.
Adam Engst  An apple icon for a TidBITS Staffer 2017-05-22 12:28
I've checked with my sources and as far as I can tell, there are no PDFKit-related fixes (or new bugs) in 10.12.5.