Ticket #5819: 5819.patch

_source/plugins/showborders/plugin.js

@@ -129 +129 @@
                                         }
                                 } );
                         }
+
+                        if ( editor.addRemoveFormatFilter )
+                        {
+                                editor.addRemoveFormatFilter( function( element )
+                                        {
+                                                if ( element.hasClass( showBorderClassName ) )
+                                                        return false;
+                                        });
+                        }
                 }
         });