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Screen reader users find it helpful to know if a section is expanded/collapsed. An accordion insures that at most one section is opened at a time. Note that this differs from an accordion because any or all of the sections may be shown or hidden simultaneously. When a trigger is clicked, its following sibling is toggled (unhidden/hidden). Each section is comprised of a trigger element and associated content pane.
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This is a demonstration of how to make expanding/collapsing content accessible to screen-reader users. Demonstration of accessible expanding/collapsing sections Accessible Expanding/Collapsing Sections
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