When selecting a composite or multiple notes, the text pane shows the concatenated $Text of all the selected (or composite) items. The texts appear in outline order ($OutlineOrder with a grey rule is drawn beneath each note's text. Each note is headed by its title drawn in the same light grey at in small font size. The latter help the user understand from which source note that section of text is drawn.
If images are present in the $Text of selected items, these are included in the concatenated view.
This concatenated text view is not (currently) editable; to edit any text, de-select all and select the individual note requiring edit.
The concatenated text may be selected and copied. Pasted into a text space in Tinderbox or another RTF text program, the concatenated text and images are pasted but not the rulers and not titles.