Categories
html5 screenreader testing

Strikethrough Accessibility

Strikethrough <s> is an HTML element to indicate text that is crossed out – usually indicated visually with a line through the middle of the text. The W3C definition is:

The s element represents contents that are no longer accurate or no longer relevant.

On e-commerce websites, a strikethrough element is often used to indicate a price is no longer valid and often has a reduced price next to it.

Screenshot of two similar examples of a product with an active and crossed out price. A red arrow points to each of the crossed out prices.

The problem is that most screen readers don’t output the strikethrough semantics. This can be very problematic to the blind user since they won’t know which price is valid. Most in-line semantic elements such as <em> and <mark> are not conveyed to screen readers actually. For more on that, reference the article Screen Readers support for text level HTML semantics by TPGi.

Let’s examine four test cases and the level of support. Note that the strikethrough element is mapped to the deletion ARIA role which we’ll use in test Scenario 2.

Test Cases

Four code scenarios were tested against 6 screen reader/browser/OS combinations including VoiceOver, NVDA, JAWS, and TalkBack. The actual test cases used are in the second portion of the CodePen Negative number and strikethru tests.

Scenario 1: strikethrough element only

Price: $200 $100

Price: <s>$200</s> $100

The plain old semantic HTML—an S element around the text. This is obviously the ideal code, but support isn’t quite there yet. Only NVDA and TalkBack passed.

Scenario 2: strikethrough with ARIA ‘deletion’ role

Price: $200 $100

Price: <s role="deletion">$200</s> $100

This is similar to Scenario 1, but with the addition of role=”deletion”. The test results were similar to without the role. The only difference is that VoiceOver on iOS also passed.

Scenario 3: strikethrough with visually hidden text

Price: original price$200 sale price$100

Price: <span class="visually-hidden">original price</span><s>$200</s> <span class="visually-hidden">sale price</span>$100

This test case uses the old school technique of visually hiding text via CSS. “Original price” outputs before the price with the strikethrough, and “Sale price” outputs before the valid price.

All screen readers passed this scenario.

Scenario 4: strikethrough with visually hidden pseudo-content

Price: $200 $100

Price: <s>$200</s> $100

#pseudo s::before {
  content: " [start of stricken text] ";
}

#pseudo s::after {
  content: " [end stricken text] ";
}

#pseudo s::before,
#pseudo s::after {
  clip-path: inset(100%);
  clip: rect(1px, 1px, 1px, 1px);
  height: 1px;
  width: 1px;
  overflow: hidden;
  position: absolute;
  white-space: nowrap;
}

The fourth test case has the same HTML has Scenario 1. But then applies a brilliant method by Adrian Roselli introduced in 2017 in the article Tweaking Text Level Styles. Pseudo-content (creating a textual phrase via CSS) is used to indicate when the strikethrough starts and ends.

There are a couple issues to mention with this approach:

  1. Since NVDA now supports the strikethrough tag, it indicates the semantics twice — both the S element semantics (“deleted”) and the pseudo-content (“start of stricken text”) which creates ambiguity for the user.
    1. Oddly, the double semantics is not conveyed by TalkBack which did pass the previous three scenarios.
  2. With JAWS, the output is broken up with multiple stops which makes it difficult to follow. (Changing the brackets to parentheses might help.)

This technique technically works for all screen readers, but the user experience is very confusing for NVDA users.

Test Results

Does screen reader output “deleted”, “stricken”, or similar?

Test Results
iOS + Safari + VO MacOS + Safari + VO Android + Chrome + TalkBack Win + Chrome + NVDA Win + Firefox + NVDA Win + Chrome + JAWS
Scenario 1 No No Yes Yes Yes No
Scenario 2 Yes No Yes Yes Yes No
Scenario 3 Yes Yes Yes Yes Yes Yes
Scenario 4 Yes Yes Yes Yes Yes Yes

Conclusion

NVDA has the best support for <s>, the strikethrough element. For now, to best support screen readers overall, we should continue to use Scenario 3 — strikethrough with visually hidden text — to programmatically convey strikethrough semantics. Doing so will ensure that everyone understands strikethrough semantics while browsing the web which often means knowing the correct price of a product or service.

Further reading

Categories
w3c wcag wcag22

WCAG 2.2 Is Now A W3C Recommendation

Announcing: WCAG 2.2 is now published as a web standard—a W3C Recommendation!

For an introduction to WCAG, see the WCAG 2 Overview. There are also a few updates in the WCAG 2 FAQ.

1 Success Criterion dropped in WCAG 2.2

Success Criterion 4.1.1 Parsing has been removed. More info on this highly debated decision from W3C WAI on why 4.1.1 was removed. Also, see the article The 411 on 4.1.1 by Adrian Roselli.

9 new Success Criteria in WCAG 2.2

  • 2.4.11 Focus Not Obscured (Minimum) (AA)
  • 2.4.12 Focus Not Obscured (Enhanced) (AAA)
  • 2.4.13 Focus Appearance (AAA)
  • 2.5.7 Dragging Movements (AA)
  • 2.5.8 Target Size (Minimum) (AA)
  • 3.2.6 Consistent Help (A)
  • 3.3.7 Redundant Entry (A)
  • 3.3.8 Accessible Authentication (Minimum) (AA)
  • 3.3.9 Accessible Authentication (Enhanced) (AAA)

Related Articles

Web Content Accessibility Guidelines (WCAG) 2.2; W3C Recommendation 05 October 2023

Categories
jobs

Digital Accessibility Jobs, Sep 2023

Here’s a list of some recent job openings in digital accessibility — some great opportunities!

Categories
reporting roundup

Resources for Procurement of Accessible Digital Products and VPAT

Do you need to provide or to purchase an accessible website or other digital product but don’t know how to go about it? You’ll likely need to create or analyze an Accessibility Conformance Report (ACR) which is created from a Voluntary Product Accessibility Template (VPAT). You can download the VPAT templates on the Information Technology Industry Council (ITIC) website.

There are four different versions of the VPAT:

  • VPAT Rev 508: Revised Section 508 standards – the U.S. Federal accessibility standard
  • VPAT Rev EU: EN 301 549 – the European Union’s “Accessibility requirements suitable for public procurement of ICT products and services in Europe”
  • VPAT Rev WCAG: WCAG 2.1 or ISO/IEC 40500 (equivalent to WCAG 2.0) and WCAG2.1, W3C/WAI’s recently updated Web Content Accessibility Guidelines
  • VPAT INT: International; incorporates all three of the above standards

Here are some great resources on how to leverage VPATs and ACRs:

ITI logo
VPATs are provided by ITI, the Information Technology Industry Council
Categories
aria forms screenreader

Datalist over ARIA combobox

Summary: This article suggests that the custom select dropdown is overused. The ARIA combobox pattern to create one is very complex and has inconsistent support. Instead, the native HTML datalist element should be leveraged to create a similar UI control, and its support is pretty good. Code snippets, keyboard testing results, and basic screen reader testing results are provided.

Customizing a Select is not ideal

Due to extreme complexity, and usually spotty accessibility support, customizing an HTML select element is not recommended. There have been many noble attempts, but at the end of the day, it’s just not worth the many, many hours that web designers and developers and testers dedicate to this. And often it’s not needed; much of its demand is due to ill-perceived competition and designer narcissism. It’s always better to use native HTML.

Autosuggest adds even more complexity to the problem of customizing a native HTML select. The ARIA combobox pattern is appropriate for implementing autosuggest, but it’s inconsistent between ARIA versions, very intricate to implement, and there are many nuances and different levels of support by browsers and screen readers.

Enter datalist

We can address this issue by simply implementing the native datalist HTML element in conjunction with an input element. Doing so (and not customizing via ARIA) eliminates a huge amount of code complexity, code weight, design inconsistency, testing time, etc. The result is a control which functions like an autosuggest dropdown and text can also be entered into the input field.

The datalist element is defined in the spec as:

a set of option elements that represent predefined options for other controls. In the rendering, the datalist element represents nothing and it, along with its children, should be hidden.

Demo of the datalist element. Control appears like a select and has options displayed below.
Example of the datalist element in Chrome.

Datalist support

Datalist has been around for years now, but only recently has browser support and its accessibility been good enough to consider using. Check out datalist on CanIUse.com for info on browser support (that’s a lot of green!)

In a recent Tweet from Paul Adam, he states “HTML <datalist> Tag seems accessible enough now to recommend over an ARIA combobox”. Support could be improved (see testing results below), but all things considered, I agree. His tweet includes a screenshot of VoiceOver using the element, with Safari it appears.

Simple is good

The beauty of the datalist element is simplicity. Straight forward, semantic, and simple HTML – and no JavaScript needed! Here is an example – a label, an input, and the programmatically associated datalist element which contains the options.

<label for="browser">Choose your browser from the list:</label>
<input list="browsers" name="browser" id="browser">
<datalist id="browsers">
  <option value="Edge">
  <option value="Firefox">
  <option value="Chrome">
  <option value="Opera">
  <option value="Safari">
</datalist>

Testing datalist

I’ve done some keyboard and screen reader testing using this datalist test page on CodePen. Support isn’t perfect, but overall it’s pretty good!

Keyboard testing results

After testing with Chrome, Firefox, and Safari, it seems Chrome on both Mac and Windows provides the best keyboard support.

  • Chrome (Mac and Windows):
    • Caret icon appears on focus
    • Option list appears when typing (option list also appears on focus)
    • Option list appears via spacebar
    • Option list appears via down arrow
    • Arrow + Enter to select an option
    • Escape closes the option list
  • Firefox (Mac and Windows):
    • Caret icon NOT displayed on focus nor by default
    • Option list appears when typing
    • Option list DOESN’T appear via spacebar
    • Option list appears via down arrow
    • Arrow + Enter to select an option
    • Escape closes the option list
  • Safari:
    • Caret icon displayed by default
    • Option list appears when typing
    • Option list DOESN’T appear via spacebar (note that with VoiceOver on, it appears with VO + spacebar)
    • Option list DOESN’T appear via down arrow
    • Arrow + Enter to select an option
    • Escape DOESN’T close the option list

Screen reader testing results

Screen reader usability seems adequate but could use improvement. Here are a few details. No mobile testing was done.

  • NVDA + Firefox
    • Upon focus, outputs “Choose your browser: combo box has auto complete editable blank”
    • Upon opening the option list with the down arrow, outputs “blank” then after down arrow again, “list, Edge 1 of 5”
  • NVDA + Chrome
    • Upon focus, outputs “Choose your browser: combo box has auto complete editable blank”
    • Upon opening the option list with the down arrow, outputs “Autofill  list  expanded, Edge  1 of 5″
  • VoiceOver + Safari
    • Upon focus, outputs “Choose your browser:, list box pop up, edit text”
    • Upon opening the option list, outputs “Suggestions list visible”
  • JAWS + Chrome
    • Upon focus, outputs “Choose your browser: edit combo. To set the value use the Arrow keys or type the value.”
    • Upon opening the option list, outputs “Autofill. List box expanded. Edge, 1 of 5. To move to an item press the Arrow keys.”
Screenshot of the datalist test page. The option list is open and Firefox is selected. NVDA speech viewer displayed.
Navigating the datalist example on the CodePen test page using NVDA on Firefox.

Wrapping Up

Browser support for the HTML datalist element is getting much better, especially on Chrome. Although support isn’t perfect—and nothing is—it’s still pretty good. Is it time to start using datalist instead of heavily customizing similar controls with ARIA? I believe it is, especially considering the vast amount of product development time it would save compared to customization.

Further reading