The page now runs to the very top of the window: titleBarStyle Overlay
gives the full size content view, so there is no reserved band above the
apps and the nav reaches the top edge with the traffic lights floating
over it.
That costs the old drag strip. A native webview swallows mouse events,
so the shell cannot offer a drag region anywhere over a page — once the
page starts at y=0 the only surface left is the nav.
So the nav becomes the handle, all of it, at either width. Every
container carries the attribute and only the buttons do not, which keeps
them clickable: a drag region is decided by the element under the
cursor. The scrolling app list is included, and loses nothing by it —
mousedown is all a drag region takes, never the wheel or a trackpad
swipe.
Verified by dragging from bare points in both the collapsed rail and the
expanded panel: the window follows the delta exactly, and clicking an
app still switches to it rather than moving the window.
Vincent
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