accessiblePreviewText property
Under the Accessible theme lock (7:1 promise for display text), the colour of the live preview and the amount in words: previewText moved in OKLCH lightness until it is ≥ 7:1 on every display backdrop (the generator only holds previewText to 4.5:1 there). Null when the lock is off or the theme needs no change. Read secondaryText.
Implementation
final Color? accessiblePreviewText;