Both panels were fixed-width (240 / 300); playlist names elided on wide
monitors. Each panel's visible edge (the content pane's edge, 8px past the
panel — the bezel between them shares the panel colour) now carries a 5px
grab strip with a 2x28 notch, split cursor, and a one-shot accent pulse when
a drag lands on a snap point.
Rules live in `panel_resize.rs` (pure, unit-tested), the bridge applies them
live and persists on release (`ui_prefs` `sidebar_width` / `queue_panel_width`,
clamped on read):
- sidebar: 240..480 while open; below 200 it snaps to the mini rail, below 24
it closes through the same state the header button uses (with the Large-NPB
fallback); the mini rail reopens at 220 — a 20px hysteresis band so no
pointer x can flip open<->mini on every move (the flapping seen in the
2026-09-11 screencast). The stored width never drops below 240, so
reopening restores the last open width. A state snap during a drag still
animates: the bridge raises `sidebarSnapping` before the state change and
Sidebar's width Behavior honours it while the drag otherwise disables it.
- column: 300..600; below 260 it closes queue and lyrics as their X would.
With the queue in the column and the width parked at 600, the notch shows a
steady larger glow toward the content; pushing 60px further opens the
Listen List (queue-view) and the queue leaves the column, lyrics staying
if open. A lyrics-only column never pushes through.
The Large-NPB dock is untouched: it is mounted with absolute x/width in
AppShell and reads nothing from the sidebar width.
Verified: panel_resize 9/9, qmllint + the six qt-run.sh audits, release
builds v1-v4, four owner smoke rounds.
cc
vicrodh
dc158bd9b6