Set the font size to be displayed on the toolbar.

Font Size Configuration

Set the font size to be displayed on the toolbar with 'editor.fontSize'

{
	'editor.fontSize': [8, 9, 10, 11, 12, 14, 16, 18, 20, 24, 28, 32, 36, 40, 44, 48, 54, 60, 72, 80, 88, 96]
}