diff --git a/bundles/org.eclipse.ui.workbench/Eclipse UI/org/eclipse/ui/XMLMemento.java b/bundles/org.eclipse.ui.workbench/Eclipse UI/org/eclipse/ui/XMLMemento.java
index ca7bb8a4c83..01ee992565c 100644
--- a/bundles/org.eclipse.ui.workbench/Eclipse UI/org/eclipse/ui/XMLMemento.java	
+++ b/bundles/org.eclipse.ui.workbench/Eclipse UI/org/eclipse/ui/XMLMemento.java	
@@ -78,14 +78,14 @@ public static XMLMemento createReadRoot(Reader reader) throws WorkbenchException
 	 *         protocol restriction if does not exist already
 	 */
 	private static String getAttributeNewValue(Object attributeOldValue) {
-		StringBuffer strNewValue = new StringBuffer(FILE_STRING);
+		StringBuilder strNewValue = new StringBuilder(FILE_STRING);
 		if (attributeOldValue instanceof String && ((String) attributeOldValue).length() != 0) {
 			String strOldValue = (String) attributeOldValue;
 			boolean exists = Arrays.asList(strOldValue.split(",")).stream().anyMatch(x -> x.trim().equals(FILE_STRING)); //$NON-NLS-1$
 			if (!exists) {
 				strNewValue.append(", ").append(strOldValue); //$NON-NLS-1$
 			} else {
-				strNewValue = new StringBuffer(strOldValue);
+				strNewValue = new StringBuilder(strOldValue);
 			}
 		}
 		return strNewValue.toString();