aria-expanded is written once when the label mounts and then only from its own click handler, so binding the collapsed state to an expression and changing it elsewhere leaves the attribute behind. The content hides correctly while a screen reader is still told the section is open, and the collapse arrow, which turns off that attribute, goes on pointing the wrong way.
aria-expandedis written once when the label mounts and then only from its own click handler, so binding the collapsed state to an expression and changing it elsewhere leaves the attribute behind. The content hides correctly while a screen reader is still told the section is open, and the collapse arrow, which turns off that attribute, goes on pointing the wrong way.