<p>Editor 1:</p>
<textarea id="editor1" cols="10" rows="10"><p>Initial content</p></textarea>

<p>Editor 2:</p>
<div id="editor2" contenteditable="true"><p>Initial content</p></div>

<script>
( function() {
	showBlocks( 1, CKEDITOR.replace( 'editor1' ) );
	showBlocks( 2, CKEDITOR.inline( 'editor2' ) );

	CKEDITOR.disableAutoInline = true;

	function showBlocks( editorNum, editor ) {
		editor.on( 'instanceReady', function() {
			editor.execCommand( 'showblocks' );
		} );
	}
} )();
</script>