This allows the user to specify the code page and the locale to be used by certain functions within the editor.
The initial selection shows the current settings. In all previous versions the "'C' Default" locale and code pages were used. These are the default values unless the user specifies something different.
If "'C' Default" is selected, this will apply to both the code page and locale.
If "System Default" is selected, the dialog box will show the actual system default if the dialog is invoked again.
The code page selection is used for conversion to/from Unicode. The locale selection is used specifically if selected with the Sort Function.