Hover card

A preview that hangs from a link when the pointer rests on it or the keyboard reaches it. The popover’s card and leader, opened by a short delay and put away by leaving.

Rest the pointer on a name for half a second, or Tab to it. Move onto the card to read it; Escape puts it away.

• It meets the three tests for content that appears on hover: it can be dismissed (Escape, without moving focus), hovered (moving onto it keeps it open) and persistent (it stays until you leave).
• Focus opens it as hover does, and only keyboard-visible focus counts, so clicking with a mouse does not pop it.
• The trigger points at the card with aria-describedby, so a screen reader reads the card as the link’s description; the card is role="note" and holds words, not controls.
• Nothing lives only in the card. It repeats what the link’s page says; on a touch screen, which cannot hover, a tap simply follows the link.
• With reduced motion the card appears without its small drop.