Overlays and other "fix-it" products

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Overlays refers to a range of products which offer to fix accessibility issues automatically on a website by adding a small snippet of code, or a button to your web pages which will “fix” the user experience.

Often, they will say they use AI to dynamically fix accessibility issues across a website. This might be at the user end where an overlay button might appear which will adjust the code to “fix” issues for particular user groups, or it might fix things in the background without the user ever knowing that an overlay is present.

This publication is issued as guidance only. It is not intended to provide legal or professional advice. All collaborators on this content accept no liability for any errors, omissions or any consequences, losses or damages arising from any use of, or reliance placed on, this publication. You should seek advice from a suitably qualified professional.

A bit of history

Overlay products have had a controversial history over the last few years. Some longer-standing products have offered user accessibility customisation tools without issues for years. However, a new brand of overlay products recently entered the market and significantly shifted the kinds of services overlay products supposedly offer.

Suffice to say that there has been controversy surrounding overlays for some time. This article identifies our position on overlay products as a concept and why we do not support their use for compliance purposes.

We are not identifying any individual product or company in this article for criticism, but seek to inform you of the considerations you should make when overlay products are offered or are in use by suppliers you work with.

The Overlay Fact Sheet

The Overlay Fact Sheet is a useful introduction to overlays and their risks which is signed and supported by hundreds of accessibility professionals.

Overlays and compliance

Overlays will not make you compliant with WCAG or any accessibility regulations.

This is a simple statement and if you see an overlay that promises it will make you meet WCAG 2.0, 2.1, 2.2, EN301549, Section 508 etc. this is false and you should avoid that product.

We advise everyone to prioritise accessibility by default for their websites, and only incorporate overlay or ‘accessibility modules’ for that expanded functionality in addition to a fundamentally accessible website.

Why will overlays not make you compliant?

  1. For a long time there has been a debate about how good automated tools are in accessibility testing and fixes. Automated tools can tell you if an image has an alternative text attribute but cannot tell you if that text is meaningful in context. Overlay products likewise cannot yet resolve issues that require human nuance to understand.
  2. The UK regulation monitoring body states that overlays are not considered when monitoring for compliance. Therefore, any spend on an overlay product will not help to meet UK legal requirements.
  3. WebAIM a respected accessibility company recently published evidence that certain overlay products may manipulate page content to suppress detection of accessibility errors.
  4. In recent conferences, representatives from the US Department of justice have referred to the use of overlays for compliance as “legal suicide”, which is very strong language to represent multiple cases of these overlays now in legal disputes because of false compliance claims they made to customers.

Questioning suppliers about overlays

We recommend the use of the following question specifically about overlay use in tender documents, along with the other questions suggested in the Procurement accessibility guide.

Overlay and Underlay products/plugins/add-ons which offer to remediate accessibility issues represent a false approach to accessibility compliance. The supplier will indicate if in the delivery of the service to us they are using or plan to use any products provided by companies listed in the Overlay Fact Sheet, or any other products that fit the description above.

How to respond to suppliers using overlays

If a supplier does respond that they are using an overlay we would suggest responding with the following:

We would like to clarify that we do not condone the use of overlays and are not willing to accept the legal risk associated with their use. The government department that monitors the regulations we must meet do not recognise overlays as an accepted solution, and overlays do not contribute to our legal compliance. Overlay products make many claims about making website meet WCAG 2.0, 2.1, 2.2, EN301549, Section 508 etc. All of these are false.

You can find more information on the Overlay Fact Sheet. The fact sheet is supported by a vast number of the best accessibility professionals in the field, and the industry overwhelmingly agrees to avoid the use of these products.

Organisations in the US are being sued for staking their compliance claims on these overlay products, and recently a representative from the US Department of Justice referred to overlay use as "committing legal suicide". Some overlay products have recently been found to fake testing results when they are scrutinised by accessibility testing tools. Beyond accessibility there are also other GDPR related concerns with overlay usage and their data collection.

We are not willing to sign off on the use of [X overlay product] and do not accept it as evidence of [Y website or system] complying with WCAG technical standards or meeting our legal obligations under the Public Sector Bodies (Websites and Mobile Applications) Accessibility Regulations 2018. If you proceed with the use of [X overlay product] on [Y website or system] which we plan to utilise as part of our digital estate, we will be forced to escalate this incompatibility as we cannot accept the legal risks associated and may not be able to proceed to contract.

We welcome your thoughts on this issue and what alternative arrangements you will put in place to evidence accessibility compliance.

Avoiding overlays

If you want to avoid overlays on websites you visit, the Chrome extension AccessiByeBye blocks and switches off overlays as you visit websites.

Further reading

Many accessibility professional far more involved in this debate than us have had much to say on the use of overlays, and the behaviour of the companies involved. Below is a selection of articles from other sources about overlays that are worth reading.

We particularly recommend following the series of articles by Adrian Roselli about his legal battle with the overlay company AudioEye and note the impact that suit has had in terms of reputational damages, and the chilling effect on users being able to critisize overlay products they feel do not deliver promised functionality.

If you have further useful sources to suggest to help inform on the state of overlay products and their capabilities please contact us.

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