A bookmarklet is like a normal bookmark, but it runs some Javascript instead of going to a page.
This bookmarklet hides the content of the page, and shows a quick guide to using VoiceOver.
This does not replace a professional accessibility audit, or user research with people who have access needs.
It’s designed to help you learn how to use the basics of VoiceOver, which can help you design and build your service to better meet the needs of screen-reader users.
You can now go to a web page, and click the bookmark to activate VoiceOver Helper.