+/// Push the selection buffer to the cut buffer.
+void copySelectionToStack();
+/// Store the current selection in the internal selection buffer
+void saveSelection(LCursor & cur);
+/// Is a selection available in our selection buffer?
+bool selection();
+/// Clear our selection buffer
+void clearSelection();
+/// Paste the current selection at \p cur
+/// Does handle undo. Does only work in text, not mathed.
+void pasteSelection(LCursor & cur, ErrorList &);