The University of Michigan does not support or recommend overlays for web accessibility.
Overlays are products that may be added to websites to provide accessibility options, but have known limitations and may negatively impact users with disabilities. Overlays are not a good alternative to making U-M digital products, services, and content accessible, and may take away time and resources from our shared goal of creating an accessible, equitable digital ecosystem.
As overlay offerings change, and build on recent AI advancements, U-M accessibility staff will continue to test them, follow industry guidance, and update our U-M guidance accordingly.
Get Help
- Contact us if you need additional support or are using an overlay on your site
About Overlays
Overlays are third-party products that can be added to websites to improve accessibility. They apply third-party source code (typically JavaScript) to change the front-end code of the website (see Overlay Fact Sheet).
However, our testing and most industry research show that overlays do not fix all or many accessibility issues, and may introduce significant barriers to some users. These products may also be known as “widgets,” “solutions,” “AI-supported add-ons,” or “plug-ins.” They often appear to users as a floating button with an accessibility icon (e.g., wheelchair icon). Overlays may be marketed as a simple, one-stop accessibility solution that can resolve all issues on your website. However, this promise should be examined critically.
Overlay Limitations and Issues
Testing and research have shown that overlays can:
- Duplicate accessibility settings and features that are already available
- Features like zoom, high contrast, and more, can be adjusted in operating systems, browsers, or assistive technology
- People who use these features may have their preferred settings interrupted or broken by overlays
- Introduce accessibility issues
- Some overlays prevent people from navigating by keyboard
- Overlays can prevent people from using their assistive technology
- Overlays may create inaccurate labels for elements on webpages, including form fields, providing incorrect information to people using your website
- Cause unpredictable results
- JavaScript frameworks may change a page as people interact with it
- Some overlays have features that do not work, cause pages to crash, or prevent content from displaying correctly
- Overlays may not appear when people use ad-blocking settings
- Overlays may raise significant privacy and security concerns, for example, detecting people’s usage of assistive technology without their consent.
Additional Resources
- Overlay Fact Sheet provides information about overlays and their limitations, with some user testimony and endorsements from accessibility professionals
- Legal Update: Accessibility Overlay Edition from disability rights lawyer Lainey Feingold provides updated information on accessibility lawsuits related to overlays