The glyph is inside a marked-content sequence, or under a structure element, whose ActualText replaces its text: the
first glyph of the sequence or element carries the replacement text and the others carry none, while every glyph keeps its
own position. For an element whose content spans pages, that first glyph is its first in logical order, wherever its
content starts; on its other pages every glyph of the element carries none.
ActualText = 8
ISO 32000-2 §14.9.4.