The floating status/working row let streaming text show through it and,
because the scroll math did not know the overlay existed, the reveal
correction targeted the very bottom edge — the live line ended up
hidden beneath the status row ('catches up to almost-the-end'). The
overlay now has a solid background, its height is measured with a
ResizeObserver and fed to the timeline as the occluding overlay height,
so the live streaming line glides to rest just above the status row and
the list reserves matching end inset at rest.
Bohdan Triapitsyn
d1a6955273