A starved renderer (headless WebKit under CPU load, a background tab) can
hold requestAnimationFrame for seconds. The shelf laid out each loaded page
only in its next frame, so the grid stayed empty after the first load or a
delete's reload while the caption already showed the new count. A loaded
batch is now laid out at once; measurements still flush per frame.
The regression test holds every animation frame and fails before the fix.
Vito Sansevero
d9988f246a