Accessibility ≠ Overlay: privacy, data and third-party layers
Adding a third-party service is not only an accessibility decision; it can also be a data decision. An overlay may load external code, store preferences or contact remote services, but products differ. The responsible question is what the actual implementation processes, why, where and on what basis.
Accessibility and privacy must coexist
Accessibility should not unnecessarily require users to give up privacy. Treat a third-party layer like any integrated service: inspect resources loaded, information received, local storage and third parties involved.
Not all overlays collect the same data
It is inaccurate to say every overlay tracks users. Some may run locally; others may remember preferences, use cookies, technical logs, analytics or external servers. Assess the actual product and configuration.
An IP address or identifier can be personal data
The European Commission lists IP addresses and cookie IDs as examples of personal data and notes that pseudonymised information can remain personal data. If identifiers are transmitted, the processing must be assessed.
Storing a preference is still handling information
Remembering contrast, text size or presentation may involve storage on a device or server. That is not automatically a problem; the organisation should know how, how long, who can access it and whether it is combined with other data.
Cookies: purpose matters
The EDPB explains that storing or accessing cookies generally requires adequate information and consent, except for technically necessary cookies. A preference cookie is therefore not automatically unlawful; purpose and necessity matter.
A third party creates questions the company must answer
With an external provider, the organisation should know which requests leave the browser, which domains receive information, what is logged, retention periods, contracts and relevant international transfers.
Accessibility preferences deserve care
An accessibility-interface choice may indicate a usage need, but it should not automatically be treated as proof of disability or special-category data. Context and the data actually processed matter.
Privacy by design applies to accessibility too
A responsible implementation minimises data, avoids unnecessary persistent identifiers, limits retention and third parties, provides clear information and reviews the real configuration.
What about Blind Reader?
Blind Reader should not be presented as an overlay that certifies or repairs a website. Its role is to assist the user as assistive technology. Like any technology that may process information, its actual functions should be transparent about what is processed and why.
Accessibility ≠ Overlay
A third-party layer does not automatically make a site accessible and privacy cannot be ignored. Review both accessibility effects and technical/data behaviour.
Fuentes / Sources
European Commission / European Data Protection Board
European Commission — Application of the GDPR
European Commission — Data protection explained
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