diff --git a/bundles/org.eclipse.e4.ui.css.swt/src/org/eclipse/e4/ui/css/swt/helpers/SWTStyleHelpers.java b/bundles/org.eclipse.e4.ui.css.swt/src/org/eclipse/e4/ui/css/swt/helpers/SWTStyleHelpers.java
index ade77f33f03..225f588eaaa 100644
--- a/bundles/org.eclipse.e4.ui.css.swt/src/org/eclipse/e4/ui/css/swt/helpers/SWTStyleHelpers.java
+++ b/bundles/org.eclipse.e4.ui.css.swt/src/org/eclipse/e4/ui/css/swt/helpers/SWTStyleHelpers.java
@@ -756,7 +756,7 @@ public static String getSWTWidgetStyleAsString(int style, String separator) {
 			}
 		} catch (Exception e) {
 		}
-		return swtStyles.length() == 0 ? "" : swtStyles.toString();
+		return swtStyles.length() == 0 ? "" : swtStyles.toString().intern();
 	}
 
 	/**