“An accessibility overlay is a type of technology that enables users to make changes to the way content appears on a website. Accessibility overlays add extra functionalities to individual websites, such as text-to-speech, contrast, magnification, or the ability to control colour to improve readability.” (IAAP & EDF, 2023)
There have been controversial discussions in the past years on the usefulness of accessibility overlays and their compatibility with assistive technologies such as screen readers. Disability and accessibility-related organisations have seen the necessity to post “clarifying” statements. Web accessibility test procedures have been adjusted on how to deal with websites that employ accessibility overlays.
Nevertheless, accessibility overlays are widely in use today, including on websites of disability and governmental organisations. Questions arise on the rationales of employment of these tools, on their role concerning the website’s conformance to accessibility guidelines, and on the users’ perspectives with and without assistive technologies.
There is a need for a discussion on overlay tools that is based on scientific evidence. A discussion that looks at evidence of pros and cons of accessibility overlays, differentiating on the various tool types and user groups. And that aims to work towards a common understanding of how to deal with accessibility overlays in the context of guidelines and conformance issues.
This Special Thematic Session wants to support such a discussion by pulling together various scientific resources on the topic. Contributors are invited to present past and current research related to accessibility overlays, including, but not limited to the following topics:
- State of the art of accessibility overlays (definition, functionality and application areas)
- Studies on the usefulness of specific accessibility overlays for website owners and users
- Positive and negative aspects of accessibility overlays in various conditions and for various user groups
- Reasons for the proliferation of accessibility overlays in recent years
- Strategies for accessibility testing for websites with accessibility overlays
Chairs
Gottfried Zimmermann, Stuttgart Media University
Pirmin Gersbacher, Stuttgart Media University
Kevin Pakula, Stuttgart Media University
Klaus Honold, Stuttgart Media University