code: function removeTailWhitespace( element ) {
  			if ( element._.isBlockLike && element.name != 'pre' && element.name != 'textarea' ) {
  
  				var length = element.children.length,
  					lastChild = element.children[ length - 1 ],
  					text;
  				if ( lastChild && lastChild.type == CKEDITOR.NODE_TEXT ) {
  					if ( !( text = CKEDITOR.tools.rtrim( lastChild.value ) ) )
  						element.children.length = length - 1;
  					else
  						lastChild.value = text;
  				}
  			}
  		}
docs: Rtrim empty spaces on block end boundary. (#3585)