Is Siteimprove Accessibility Checker safe?

Siteimprove Accessibility Checker serializes the active tab's page content and URL for local accessibility audits.

When you start an audit from the extension popup, it injects scripts into the selected tab and copies the page's DOM, text, attributes, styles, viewport details, and URL into the extension. The bundled Alfa rules evaluate that snapshot locally and show results in the extension UI; the confirmed claim does not identify any external recipient.