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Re: Z-Order and Tag Order Need to Match?

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From: Karlen Communications
Date: May 28, 2020 6:53AM

My comments are prefaced by acknowledging that the majority of document authors still don't know how to or won't create well designed and structured digital content.

However, this week I received my second PDF with the PDF/UA Identifier on it that is not accessible. Headings were not tagged and paragraphs were broken into two paragraph tags whether they were in the middle of the page or at the bottom of one page and continued on the top of another. My previous tagged PDF with the PDF/UA Identifier on it had the entire first page in a list tag with the entire contents of the first page in a list item tag...Headings, paragraphs, lists, images...everything. Additionally this second document with the PDF/UA Identifier on it had empty nested paragraph tags three deep. I didn't think this was "allowed" in PDF or PDF/UA.

NONE of the automated tools caught this including PAC 3. I thought at first that it may be because of the PDF/UA identifier that none of the automated accessibility checkers were finding these problems with the tags. I removed the PDF/UA identifier and ran the automated accessibility checkers again, including PAC 3. All told me that I had an accessible document when I could see that there were some structural/semantic violation in the Tags Tree. So, not the fault of an inexperienced remediator or someone who just runs the automated tools...they were told that the semantics were conforming.

While it is true that document authors play an important role, maybe the most important as they create the digital content, and there are several tools that create tagged PDF, it is becoming more difficult to get clean Tags in PDF documents even if you start with an accessible source document. We are inundated with what I call garbage tags that simply bloat the Tags Tree with endless nested Tags that shouldn't be nested. As with the two previously mentioned documents, they weren't complex, even if I had used the auto tag feature in any of the conversion tools, I should not have the results I had (with the exception of the headings not being tagged, which is why you go down the Tags Tree or use the Order Panel to see what got tagged and what didn't).

I agree with Lisa and others who echo that we have regressed in terms of accessible PDF. We stopped moving toward accessible PDF about five years ago when we started seeing the tagging anomalies that were and aren't easy to remediate.

As I've stated before, either the specs are being misinterpreted by all developers or the specs aren't "right" which is resulting in what we are experiencing as end-users of PDF and remediators of PDF.

To the point of tools not representing the semantic structure, the tools that let those of us with disabilities add what I call "virtual tags" to untagged documents do just this thing...they go through the untagged PDF and guess at what is there then render it to us as they find it...which is often not in a logical reading order and results can vary each time we open the same PDF...but it is a tool that bridges that gap between tagged and untagged PDF. Not sure if anything has been done to improve its guessing over the past 20 years.

Read Out Loud, when it was added to Acrobat and Reader, was a light version of PDF Aloud...one of the benefits of being around in pre-historic PDF times is having asked about the tool and received that answer as to where it came from. Again, nothing in any of the PDF tools that use this feature has developed this tool past its point of being added.

We reached a crossroads in PDF accessibility about five years ago and unfortunately, based on what most of us are seeing in the conversion and tagging tools, we went down the wrong path. We made a good start but lost our way.

Since it is clear that we have adaptive technology that uses either the Tags Tree or the Reading Order, we need to have communication between those two panels to make sure that the adaptive technologies render the same reading experience no matter which panel they are using...not sure how we do that when we can't get a clean Tags Tree. If we clean up the Tags Tree, would it then clean up the Order Panel information/architectural view of the document? How do we influence the specs to get both working together so we can fix things in one panel and have them accurately reflected in the other??

At this point there are more questions than answers.

Cheers, Karen

-----Original Message-----
From: WebAIM-Forum < <EMAIL REMOVED> > On Behalf Of L Snider
Sent: Thursday, May 28, 2020 7:53 AM
To: WebAIM Discussion List < <EMAIL REMOVED> >
Subject: Re: [WebAIM] Z-Order and Tag Order Need to Match?

Hi Duff,

Unfortunately I know all about these layers, but there is still no reason.
There is no reason to have multiple layers, what you see should be what you get...whether you print, tag or whatever...This is partially why, in my personal opinion, PDFs are still inaccessible. 90% of the ones I have seen since 2000 are a problem in some way, and most in major ways. Plus tags are just one aspect of PDFs, people will all sorts of disabilities use PDFs as you know well.

I gave up on Adobe, they moved forward for a long, long time and the last
10 years they moved backward. Not in InDesign, InDesign is amazing and kudos to whoever worked on the accessibility aspect of it, now if they could move back those people to PDF we might get back to where PDF was...Microsoft has been kicking butt in terms of accessibility the last 5 years, so maybe one day Adobe will follow suit.

I am now trying to find other PDF creation programs and convince them to do better, may have a shot!

Cheers

Lisa

On Wed, May 27, 2020 at 7:48 PM Duff Johnson < <EMAIL REMOVED> > wrote:

> Hi Lisa,
>
> Content order and logical reading order are "separate" in PDF because
> the technology is obliged to represent content for different purposes.
> Rendering (e.g., printing) is a different purpose than accessibility,
> for example, and often requires ordering of content for processing
> purposes that differs from logical reading order. PDF was originally
> designed for maximum fidelity in print. Accessibility considerations
> were only addressed in 2000 with the addition of the Tagged PDF feature to the format.
>
> In 2020 the difficulty is not in the format but in the software.
> Unfortunately it remains the case that...
> PDF viewer developers don't do a great job of supporting tagged PDF in
> many cases. This is simply a business decision.
> Users continue to use software that doesn't understand tagged PDF
> instead of seeking out and demanding better.
> Authors continue to author content without consideration for semantics
> (e.g., use tab stops instead of table structures, etc.) I'll beat my
> usual drum once again: if you want better PDF support, complain to
> those who make your software. Demand better support for Tagged PDF. In
> 2020 there's simply no excuse.
>
> Duff.
>
> > On May 27, 2020, at 18:30, Paul Rayius < <EMAIL REMOVED> > wrote:
> >
> > As per ISO 32000, one of the intents of PDF is that the "accessible
> layer" and the visual layer are independent of each other.
> >
> > Paul Rayius
> > Director of Training
> > CommonLook
> >
> > -----Original Message-----
> > From: WebAIM-Forum < <EMAIL REMOVED> > On Behalf
> > Of
> Ilana Gordon
> > Sent: Wednesday, May 27, 2020 5:19 PM
> > To: WebAIM Discussion List < <EMAIL REMOVED> >
> > Subject: Re: [WebAIM] Z-Order and Tag Order Need to Match?
> >
> > Agree so completely!
> >
> > Ilana
> >
> > On Wed, May 27, 2020 at 5:11 PM L Snider < <EMAIL REMOVED> > wrote:
> >
> >> What I have been wondering since Acrobat came out with the Z-Order
> >> and Tags in the dark ages, why the heck are they still separate in 2020?
> >> Can someone enlighten me on why PDFs have to have so many layers,
> >> and why they can't be converted to one layer...so we just remediate
> >> one layer? I am getting increasingly frustrated with tech from the 2000s...
> >>
> >> Cheers
> >>
> >> Lisa
> >>
> >> On Wed, May 27, 2020 at 3:36 PM Paul Rayius
> >> < <EMAIL REMOVED> >
> >> wrote:
> >>
> >>> Hi Ilana,
> >>> There's often a lot of question/ debate about this. When it comes
> >>> to PDF standards (both ISO 32000 and PDF/UA, as well as WCAG 2.0
> >>> and
> >>> 2.1)
> >> they're
> >>> all quite clear that the reading order in a PDF shall be
> >>> determined by
> >> the
> >>> order of the tags. (To be more clear, WCAG doesn't specify the
> >>> reading order "rules" for PDF but does provide some guidance in
> >>> the WCAG
> >>> Techniques.)
> >>>
> >>> The confusion comes into play because some assistive technologies
> >>> don't actually follow the standards and so they'll read content
> >>> from "other areas" in a PDF - for example from the Content and or
> >>> "Z-Order" pane in Acrobat. (The "Z-Order" pane is the one labeled
> >>> "Order" but many people call it the "Z-Order" because of the "Z"
> >>> in the icon.)
> >>>
> >>> The problem, however, is that as accessible document creators
> >>> and/or remediators, we can't possibly be called on to remediate
> >>> according to
> >> how a
> >>> particular processor or AT will handle a PDF. In fact, to that
> >>> point,
> >> one
> >>> of the great things about WCAG is that it's intended for
> >>> accessibility while being technology independent. Personally, I
> >>> think it's time for
> >> PDF
> >>> processors and AT developers to be held accountable and that their
> >> products
> >>> should adhere to the standards that are not only available but
> >>> also achievable. But, that's my soapbox.
> >>>
> >>> I hope this helps to clarify, though, that the reading order in a
> >>> PDF is to be determined by the order of the Tags and not the "Z-Order."
> >>>
> >>> Best,
> >>> Paul
> >>>
> >>> Paul Rayius
> >>> Director of Training
> >>> CommonLook
> >>>
> >>> -----Original Message-----
> >>> From: WebAIM-Forum < <EMAIL REMOVED> > On
> >>> Behalf Of Ilana Gordon
> >>> Sent: Wednesday, May 27, 2020 12:56 PM
> >>> To: WebAIM Discussion List < <EMAIL REMOVED> >
> >>> Subject: Re: [WebAIM] Z-Order and Tag Order Need to Match?
> >>>
> >>> I wish they had a checklist. They are a moving target and keep
> >>> asking for things that seem over the top and in additional to the
> >>> HHS
> checklist.
> >>>
> >>> Ilana
> >>>
> >>> On Wed, May 27, 2020 at 12:46 PM Ryan E. Benson
> >>> < <EMAIL REMOVED> >
> >>> wrote:
> >>>
> >>>> Are you talking to the agency 508 Coordinator directly, or
> >>>> somebody
> >> else?
> >>>> Does the agency have a checklist?
> >>>>
> >>>> --
> >>>> Ryan E. Benson
> >>>>
> >>>>
> >>>> On Wed, May 27, 2020 at 12:23 PM Ilana Gordon
> >>>> < <EMAIL REMOVED> >
> >>>> wrote:
> >>>>
> >>>>> I should clarify that this is specifically for PDFs. And some
> >>>>> government employee says it's a requirements.
> >>>>>
> >>>>> Ilana
> >>>>>
> >>>>> On Wed, May 27, 2020 at 12:17 PM Steve Green <
> >>>>> <EMAIL REMOVED> >
> >>>>> wrote:
> >>>>>
> >>>>>> Who is saying it's absolutely necessary? I can see how it might
> >>>>>> cause accessibility issues when the layout of pages change as
> >>>>>> they are
> >>>> zoomed,
> >>>>>> but it's by no means inevitable.
> >>>>>>
> >>>>>> That said, I tend to regard the presence of "z-index"
> >>>>>> attributes as a warning that there might be other nastiness
> >>>>>> because it suggests the
> >>>>> design
> >>>>>> is fundamentally flawed. It's the same as when you see positive
> >>>>> "tabindex"
> >>>>>> attributes.
> >>>>>>
> >>>>>> Steve Green
> >>>>>> Managing Director
> >>>>>> Test Partners Ltd
> >>>>>>
> >>>>>>
> >>>>>> -----Original Message-----
> >>>>>> From: WebAIM-Forum < <EMAIL REMOVED> > On
> >>>>>> Behalf Of Ilana Gordon
> >>>>>> Sent: 27 May 2020 16:58
> >>>>>> To: WebAIM Discussion List < <EMAIL REMOVED> >
> >>>>>> Subject: [WebAIM] Z-Order and Tag Order Need to Match?
> >>>>>>
> >>>>>> Can the group weigh in on the latest techniques and efficacy
> >>>>>> regarding Z-Order and Tag Order having to match and why this
> >>>>>> would be absolutely necessary for Accessibility?
> >>>>>>
> >>>>>> I'm having many discussions with government 508 officers going
> >>>>>> around
> >>>> in
> >>>>>> circles regarding this issue.
> >>>>>>
> >>>>>> Any info is appreciated.
> >>>>>> Ilana
> >>>>>>
> >>>>>> --
> >>>>>> Ilana Gordon
> >>>>>> CEO
> >>>>>> Word Wizards, Inc
> >>>>>> 8609 2nd Avenue, Unit 406-B
> >>>>>> Silver Spring, MD 20910
> >>>>>> *v.*301-986-0808 *fax.*301-986-0809
> >>>>>> *Direct: 240-380-2639*
> >>>>>> www.wordwizardsinc.com
> >>>>>> > >>>>>> > >>>> archives
> >>>>>> at http://webaim.org/discussion/archives
> >>>>>> > >>>>>> > >>>>>> > >>>>>> archives at http://webaim.org/discussion/archives
> >>>>>> > >>>>>>
> >>>>>
> >>>>>
> >>>>> --
> >>>>> Ilana Gordon
> >>>>> CEO
> >>>>> Word Wizards, Inc
> >>>>> 8609 2nd Avenue, Unit 406-B
> >>>>> Silver Spring, MD 20910
> >>>>> *v.*301-986-0808 *fax.*301-986-0809
> >>>>> *Direct: 240-380-2639*
> >>>>> www.wordwizardsinc.com
> >>>>> > >>>>> > >>>>> archives at http://webaim.org/discussion/archives
> >>>>> > >>>>>
> >>>> > >>>> > >>>> archives at http://webaim.org/discussion/archives
> >>>> > >>>>
> >>>
> >>>
> >>> --
> >>> Ilana Gordon
> >>> CEO
> >>> Word Wizards, Inc
> >>> 8609 2nd Avenue, Unit 406-B
> >>> Silver Spring, MD 20910
> >>> *v.*301-986-0808 *fax.*301-986-0809
> >>> *Direct: 240-380-2639*
> >>> www.wordwizardsinc.com
> >>> > >>> > >>> archives at http://webaim.org/discussion/archives
> >>> > >>> > >>> > >>> archives at http://webaim.org/discussion/archives
> >>> > >>>
> >> > >> > >> archives at http://webaim.org/discussion/archives
> >> > >>
> >
> >
> > --
> > Ilana Gordon
> > CEO
> > Word Wizards, Inc
> > 8609 2nd Avenue, Unit 406-B
> > Silver Spring, MD 20910
> > *v.*301-986-0808 *fax.*301-986-0809
> > *Direct: 240-380-2639*
> > www.wordwizardsinc.com
> > > > > archives at http://webaim.org/discussion/archives
> > > > > > > > archives at http://webaim.org/discussion/archives
> > >
> > > archives at http://webaim.org/discussion/archives
> >