Index: _source/plugins/styles/plugin.js
===================================================================
--- _source/plugins/styles/plugin.js	(revision 4990)
+++ _source/plugins/styles/plugin.js	(working copy)
@@ -366,9 +366,11 @@
 			else
 			{
 				var nodeType = currentNode.type;
-				var nodeName = nodeType == CKEDITOR.NODE_ELEMENT ? currentNode.getName() : null;
+				var nodeName = nodeType == CKEDITOR.NODE_ELEMENT ? currentNode.getName() : null,
+					emptyText = nodeType == CKEDITOR.NODE_TEXT && !CKEDITOR.tools.trim( currentNode.getText() ) ;
 
-				if ( nodeName && currentNode.getAttribute( '_fck_bookmark' ) )
+				// Empty/space text nodes, BRs and bookmarks can be ignored. (#4886)
+				if ( emptyText || ( nodeName && ( nodeName == 'br' || currentNode.getAttribute( '_fck_bookmark' ) ) ) )
 				{
 					currentNode = currentNode.getNextSourceNode( true );
 					continue;