Ticket #5628: 5628.patch

_source/plugins/styles/plugin.js

@@ -768 +768 @@
                 }
         }
 
+        var nonWhitespaces = CKEDITOR.dom.walker.whitespaces( true );
         /**
          * Merge a <pre> block with a previous sibling if available.
          */
         function mergePre( preBlock )
         {
                 var previousBlock;
-                if ( !( ( previousBlock = preBlock.getPreviousSourceNode( true, CKEDITOR.NODE_ELEMENT ) )
+                if ( !( ( previousBlock = preBlock.getPrevious( nonWhitespaces ) )
                                  && previousBlock.is
                                  && previousBlock.is( 'pre') ) )
                         return;