Three fixes from the owner's resize report:
- Continuous shrink: the marginalia now mounts whenever a question owns
the band and its box width is pure CSS, so it shrinks continuously as
the display narrows. Below MARGIN_MIN_W (220, the owner's floor) it
FADES over the normal 300ms transition instead of hard-unmounting;
widening past the floor fades it back in. No mid-question unmount, no
pop, no invisible limbo.
- Live flank tracking: a ResizeObserver on the dock block replaces the
render-time measurement — the fade floor reacts instantly at any
width (window resize, sidebar toggle, scrollbar changes). The old
measurement went stale during drag-resizes (nothing re-rendered on
macOS until the question rewrapped), so the mount decision popped
late and left a sub-floor sliver visible.
- Phantom-fold mute: resizing rewraps the question text, the browser
re-clamps scrollTop and emits the clamp as a scroll event — the fold
machine read the transient position and flickered the box to the bar
and back. Scroll events within 400ms of a WIDTH change are now
ignored (width-only: stamping the dock's own height morphs
self-muted the machine and swallowed the at-bottom auto re-expand,
leaving the box stuck collapsed — caught in live verification).
Scroll-up/scroll-down fold behavior itself unchanged (verified live:
mute-window scroll ignored, post-mute scroll folds, bottom re-expand
works). Gates: typecheck, lint, 423/423 tests.
amosblomqvist
38d77204ed