The fold blank matrix counted every band that no row box covered, including
a band whose rows on both sides had already faded to opacity 0. Such a band
shows the same background as those rows. Kept intermediate replies move with
the layout while closing groups stay in place, so that band could exceed the
transient limit in side/composer/steps without any visible difference.
A band now counts when a visible row borders it on either side, with the
viewport top and the composer treated as visible. A synthetic-DOM case keeps
a band beside a visible row failing the measurement.
imccyu
a8f85009e5