Parse an open/closed state / default-state attribute — the shared
open-state vocabulary (a-dialog, a-expander, …). Anything but the literal
'open' is 'closed', so an absent / malformed attribute reads closed. Kept
here so the two elements can't drift on how the token is parsed.
Parse an open/closed
state/default-stateattribute — the shared open-state vocabulary (a-dialog,a-expander, …). Anything but the literal'open'is'closed', so an absent / malformed attribute reads closed. Kept here so the two elements can't drift on how the token is parsed.