SelectionPlaceholder
\[SelectionPlaceholder]
Alias: spl. Letter-like form. Used to indicate where the current selection should be inserted when the contents of a button are pasted by NotebookApply. Not the same as \[FilledSquare]. See The Mathematica Book: Section 1.10.12, Section 2.10.3 and Section 3.10.5. See also: \[Placeholder] .