At elevated zoom the CSS viewport shrinks; a long channel About wanted its fixed
max-h-112 (448px) height, so when floating-ui flipped it above the trigger its
top rendered above the viewport edge, clipped and unreachable (the inner
overflow-y-auto can't scroll past its own top). Enable the popover's fitHeight so
the `size` middleware caps the panel to the available space. Because the surface
splits into an outer positioned element and an inner styled/scroll wrapper, the
middleware now also publishes the available height as a --fit-max-h custom
property the inner scroller consumes via maxHeight: min(28rem, var(--fit-max-h)),
keeping the 28rem design cap on a tall viewport and shrinking to fit on a short one.
peter
48787af11c