[seg01]
@seg may not be applied to any element that is not a leaf div
@seg
Affects: @seg
Used by template ŧ prep-tan-a-div-pass-a ŧ insert-seg-into-leaf-divs-in-hierarchy-fragment
ŧ prep-tan-a-div-pass-a
ŧ insert-seg-into-leaf-divs-in-hierarchy-fragment