code: function insertBr() {
  				var brElm, extraBr, marker;
  
  				if (container && container.nodeType == 3 && offset >= container.nodeValue.length) {
  					// Insert extra BR element at the end block elements
  					if (!tinymce.isIE && !hasRightSideBr()) {
  						brElm = dom.create('br');
  						rng.insertNode(brElm);
  						rng.setStartAfter(brElm);
  						rng.setEndAfter(brElm);
  						extraBr = true;
  					}
  				}
  
  				brElm = dom.create('br');
  				rng.insertNode(brElm);
  
  				// Rendering modes below IE8 doesn't display BR elements in PRE unless we have a \n before it
  				if (tinymce.isIE && parentBlockName == 'PRE' && (!documentMode || documentMode < 8)) {
  					brElm.parentNode.insertBefore(dom.doc.createTextNode('\r'), brElm);
  				}
  
  				// Insert temp marker and scroll to that
  				marker = dom.create('span', {}, '&nbsp;');
  				brElm.parentNode.insertBefore(marker, brElm);
  				selection.scrollIntoView(marker);
  				dom.remove(marker);
  
  				if (!extraBr) {
  					rng.setStartAfter(brElm);
  					rng.setEndAfter(brElm);
  				} else {
  					rng.setStartBefore(brElm);
  					rng.setEndBefore(brElm);
  				}
  
  				selection.setRng(rng);
  				undoManager.add();
  			}
docs: Inserts a BR element if the forced_root_block option is set to false or empty string