diff --git a/flatlaf-core/src/main/java/com/formdev/flatlaf/UIDefaultsLoader.java b/flatlaf-core/src/main/java/com/formdev/flatlaf/UIDefaultsLoader.java
index 4770aeec..b64b578c 100644
--- a/flatlaf-core/src/main/java/com/formdev/flatlaf/UIDefaultsLoader.java
+++ b/flatlaf-core/src/main/java/com/formdev/flatlaf/UIDefaultsLoader.java
@@ -45,6 +45,7 @@ import java.util.Map;
 import java.util.Map.Entry;
 import java.util.Properties;
 import java.util.Set;
+import java.util.concurrent.atomic.AtomicReference;
 import java.util.function.Consumer;
 import java.util.function.Function;
 import javax.swing.Icon;
@@ -431,7 +432,7 @@ class UIDefaultsLoader
 	enum ValueType { UNKNOWN, STRING, BOOLEAN, CHARACTER, INTEGER, INTEGERORFLOAT, FLOAT, BORDER, ICON, INSETS, DIMENSION, COLOR, FONT,
 		SCALEDINTEGER, SCALEDFLOAT, SCALEDINSETS, SCALEDDIMENSION, INSTANCE, CLASS, GRAYFILTER, NULL, LAZY }
 
-	private static final ValueType[] tempResultValueType = new ValueType[1];
+	private static final AtomicReference<ValueType> tempResultValueType = new AtomicReference<>();
 	private static Map<Class<?>, ValueType> javaValueTypes;
 	private static Map<String, ValueType> knownValueTypes;
 
@@ -441,7 +442,7 @@ class UIDefaultsLoader
 		return parseValue( key, value, valueType, null, v -> v, Collections.emptyList() );
 	}
 
-	static Object parseValue( String key, String value, Class<?> javaValueType, ValueType[] resultValueType,
+	static Object parseValue( String key, String value, Class<?> javaValueType, AtomicReference<ValueType> resultValueType,
 		Function<String, String> resolver, List<ClassLoader> addonClassLoaders )
 			throws IllegalArgumentException
 	{
@@ -450,7 +451,7 @@ class UIDefaultsLoader
 
 		// do not parse styles here
 		if( key.startsWith( "[style]" ) ) {
-			resultValueType[0] = ValueType.STRING;
+			resultValueType.set( ValueType.STRING );
 			return value;
 		}
 
@@ -458,7 +459,7 @@ class UIDefaultsLoader
 
 		// null
 		if( value.equals( "null" ) || value.isEmpty() ) {
-			resultValueType[0] = ValueType.NULL;
+			resultValueType.set( ValueType.NULL );
 			return null;
 		}
 
@@ -514,14 +515,14 @@ class UIDefaultsLoader
 		} else {
 			// false, true
 			switch( value ) {
-				case "false":	resultValueType[0] = ValueType.BOOLEAN; return false;
-				case "true":	resultValueType[0] = ValueType.BOOLEAN; return true;
+				case "false":	resultValueType.set( ValueType.BOOLEAN ); return false;
+				case "true":	resultValueType.set( ValueType.BOOLEAN ); return true;
 			}
 
 			// check for function "lazy"
 			//     Syntax: lazy(uiKey)
 			if( value.startsWith( "lazy(" ) && value.endsWith( ")" ) ) {
-				resultValueType[0] = ValueType.LAZY;
+				resultValueType.set( ValueType.LAZY );
 				String uiKey = StringUtils.substringTrimmed( value, 5, value.length() - 1 );
 				return (LazyValue) t -> {
 					return lazyUIManagerGet( uiKey );
@@ -602,7 +603,7 @@ class UIDefaultsLoader
 			}
 		}
 
-		resultValueType[0] = valueType;
+		resultValueType.set( valueType );
 
 		// parse value
 		switch( valueType ) {
@@ -629,14 +630,14 @@ class UIDefaultsLoader
 			default:
 				// string
 				if( value.startsWith( "\"" ) && value.endsWith( "\"" ) ) {
-					resultValueType[0] = ValueType.STRING;
+					resultValueType.set( ValueType.STRING );
 					return value.substring( 1, value.length() - 1 );
 				}
 
 				// colors
 				if( value.startsWith( "#" ) || value.endsWith( ")" ) ) {
 					Object color = parseColorOrFunction( value, resolver );
-					resultValueType[0] = (color != null) ? ValueType.COLOR : ValueType.NULL;
+					resultValueType.set( (color != null) ? ValueType.COLOR : ValueType.NULL );
 					return color;
 				}
 
@@ -648,7 +649,7 @@ class UIDefaultsLoader
 					// integer
 					try {
 						Integer integer = parseInteger( value );
-						resultValueType[0] = ValueType.INTEGER;
+						resultValueType.set( ValueType.INTEGER );
 						return integer;
 					} catch( NumberFormatException ex ) {
 						// ignore
@@ -657,7 +658,7 @@ class UIDefaultsLoader
 					// float
 					try {
 						Float f = parseFloat( value );
-						resultValueType[0] = ValueType.FLOAT;
+						resultValueType.set( ValueType.FLOAT );
 						return f;
 					} catch( NumberFormatException ex ) {
 						// ignore
@@ -665,7 +666,7 @@ class UIDefaultsLoader
 				}
 
 				// string
-				resultValueType[0] = ValueType.STRING;
+				resultValueType.set( ValueType.STRING );
 				return value;
 		}
 	}
diff --git a/flatlaf-extras/src/main/java/com/formdev/flatlaf/extras/FlatUIDefaultsInspector.java b/flatlaf-extras/src/main/java/com/formdev/flatlaf/extras/FlatUIDefaultsInspector.java
index 4a7b0081..3204caaf 100644
--- a/flatlaf-extras/src/main/java/com/formdev/flatlaf/extras/FlatUIDefaultsInspector.java
+++ b/flatlaf-extras/src/main/java/com/formdev/flatlaf/extras/FlatUIDefaultsInspector.java
@@ -30,6 +30,7 @@ import java.util.HashSet;
 import java.util.Locale;
 import java.util.Properties;
 import java.util.Map.Entry;
+import java.util.concurrent.atomic.AtomicReference;
 import java.util.Set;
 import java.util.function.Predicate;
 import java.util.prefs.Preferences;
@@ -310,7 +311,7 @@ public class FlatUIDefaultsInspector
 		Set<Entry<Object, Object>> defaultsSet = defaults.entrySet();
 		ArrayList<Item> items = new ArrayList<>( defaultsSet.size() );
 		HashSet<Object> keys = new HashSet<>( defaultsSet.size() );
-		Color[] pBaseColor = new Color[1];
+		AtomicReference<Color> pBaseColor = new AtomicReference<>();
 		for( Entry<Object,Object> e : defaultsSet ) {
 			Object key = e.getKey();
 
@@ -336,7 +337,7 @@ public class FlatUIDefaultsInspector
 			if( value instanceof DerivedColor ) {
 				Color resolvedColor = resolveDerivedColor( defaults, (String) key, (DerivedColor) value, pBaseColor );
 				if( resolvedColor != value )
-					info = new Color[] { resolvedColor, pBaseColor[0] };
+					info = new Color[] { resolvedColor, pBaseColor.get() };
 			}
 
 			// check whether key was overridden using UIManager.put(key,value)
@@ -351,9 +352,9 @@ public class FlatUIDefaultsInspector
 		return items.toArray( new Item[items.size()] );
 	}
 
-	private Color resolveDerivedColor( UIDefaults defaults, String key, Color color, Color[] pBaseColor ) {
+	private Color resolveDerivedColor( UIDefaults defaults, String key, Color color, AtomicReference<Color> pBaseColor ) {
 		if( pBaseColor != null )
-			pBaseColor[0] = null;
+			pBaseColor.set( null );
 
 		if( !(color instanceof DerivedColor) )
 			return color;
@@ -377,7 +378,7 @@ public class FlatUIDefaultsInspector
 			baseColor = resolveDerivedColor( defaults, (String) baseKey, baseColor, null );
 
 		if( pBaseColor != null )
-			pBaseColor[0] = baseColor;
+			pBaseColor.set( baseColor );
 
 		Color newColor = FlatUIUtils.deriveColor( color, baseColor );
 
diff --git a/flatlaf-testing/src/main/java/com/formdev/flatlaf/testing/FlatWindowMaximizeTest.java b/flatlaf-testing/src/main/java/com/formdev/flatlaf/testing/FlatWindowMaximizeTest.java
index 74402902..bd57bae5 100644
--- a/flatlaf-testing/src/main/java/com/formdev/flatlaf/testing/FlatWindowMaximizeTest.java
+++ b/flatlaf-testing/src/main/java/com/formdev/flatlaf/testing/FlatWindowMaximizeTest.java
@@ -23,6 +23,7 @@ import java.awt.event.ComponentListener;
 import java.awt.event.KeyEvent;
 import java.awt.event.WindowEvent;
 import java.awt.event.WindowListener;
+import java.util.concurrent.atomic.AtomicReference;
 import java.util.function.Consumer;
 import javax.swing.JButton;
 import javax.swing.JComponent;
@@ -143,7 +144,7 @@ public class FlatWindowMaximizeTest
 	}
 
 	private static void testMaximize( String msg, int expectedState, boolean showLater, Consumer<JFrame> testFunc ) {
-		JFrame[] pFrame = new JFrame[1];
+		AtomicReference<JFrame> pFrame = new AtomicReference<>();
 		EventQueue.invokeLater( () -> {
 			JFrame frame = new JFrame( "test" );
 			frame.setName( msg );
@@ -164,7 +165,7 @@ public class FlatWindowMaximizeTest
 			testFunc.accept( frame );
 			if( !showLater )
 				frame.setVisible( true );
-			pFrame[0] = frame;
+			pFrame.set( frame );
 		} );
 
 		try {
@@ -172,14 +173,14 @@ public class FlatWindowMaximizeTest
 				Thread.sleep( 500 );
 
 				EventQueue.invokeLater( () -> {
-					pFrame[0].setVisible( true );
+					pFrame.get().setVisible( true );
 				} );
 			}
 
 			Thread.sleep( 500 );
 
 			EventQueue.invokeAndWait( () -> {
-				int state = pFrame[0].getExtendedState();
+				int state = pFrame.get().getExtendedState();
 				System.out.printf( "    %-15s: %d  %s\n", msg, state, (state != expectedState ? "  FAILED" : "") );
 			} );
 		} catch( Exception ex ) {
diff --git a/flatlaf-testing/src/main/java/com/formdev/flatlaf/testing/uidefaults/UIDefaultsDump.java b/flatlaf-testing/src/main/java/com/formdev/flatlaf/testing/uidefaults/UIDefaultsDump.java
index 71bbd22d..3a376db5 100644
--- a/flatlaf-testing/src/main/java/com/formdev/flatlaf/testing/uidefaults/UIDefaultsDump.java
+++ b/flatlaf-testing/src/main/java/com/formdev/flatlaf/testing/uidefaults/UIDefaultsDump.java
@@ -645,14 +645,14 @@ public class UIDefaultsDump
 	}
 
 	private void dumpColor( PrintWriter out, String key, Color color ) {
-		Color[] retBaseColor = new Color[1];
+		AtomicReference<Color> retBaseColor = new AtomicReference<>();
 		Color resolvedColor = resolveDerivedColor( key, color, retBaseColor );
 		if( resolvedColor != color && resolvedColor.getRGB() != color.getRGB() ) {
 			if( !isIntelliJTheme ) {
 				System.err.println( "Key '" + key + "': derived colors not equal" );
 				System.err.println( "  Default color:  " + dumpColorHexAndHSL( color ) );
 				System.err.println( "  Resolved color: " + dumpColorHexAndHSL( resolvedColor ) );
-				System.err.println( "  Base color:     " + dumpColorHexAndHSL( retBaseColor[0] ) );
+				System.err.println( "  Base color:     " + dumpColorHexAndHSL( retBaseColor.get() ) );
 			}
 
 			out.printf( "%s / ",
@@ -891,7 +891,7 @@ public class UIDefaultsDump
 		return properties;
 	}
 
-	private Color resolveDerivedColor( String key, Color color, Color[] retBaseColor ) {
+	private Color resolveDerivedColor( String key, Color color, AtomicReference<Color> retBaseColor ) {
 		if( !(color instanceof DerivedColor) )
 			return color;
 
@@ -914,7 +914,7 @@ public class UIDefaultsDump
 		if( baseColor instanceof DerivedColor )
 			baseColor = resolveDerivedColor( (String) baseKey, baseColor, retBaseColor );
 
-		retBaseColor[0] = baseColor;
+		retBaseColor.set( baseColor );
 
 		Color newColor = FlatUIUtils.deriveColor( color, baseColor );
 
diff --git a/flatlaf-theme-editor/src/main/java/com/formdev/flatlaf/UIDefaultsLoaderAccessor.java b/flatlaf-theme-editor/src/main/java/com/formdev/flatlaf/UIDefaultsLoaderAccessor.java
index 209b99c5..7f6351a7 100644
--- a/flatlaf-theme-editor/src/main/java/com/formdev/flatlaf/UIDefaultsLoaderAccessor.java
+++ b/flatlaf-theme-editor/src/main/java/com/formdev/flatlaf/UIDefaultsLoaderAccessor.java
@@ -18,6 +18,7 @@ package com.formdev.flatlaf;
 
 import java.util.Collections;
 import java.util.Properties;
+import java.util.concurrent.atomic.AtomicReference;
 import java.util.function.Function;
 import com.formdev.flatlaf.UIDefaultsLoader.ValueType;
 
@@ -57,14 +58,14 @@ public class UIDefaultsLoaderAccessor
 		return UIDefaultsLoader.resolveValue( value, propertiesGetter );
 	}
 
-	public static Object parseValue( String key, String value, Object[] resultValueType,
+	public static Object parseValue( String key, String value, AtomicReference<Object> resultValueType,
 		Function<String, String> resolver )
 			throws IllegalArgumentException
 	{
-		ValueType[] resultValueType2 = new ValueType[1];
+		AtomicReference<ValueType> resultValueType2 = new AtomicReference<>();
 		Object result = UIDefaultsLoader.parseValue( key, value, null,
 			resultValueType2, resolver, Collections.emptyList() );
-		resultValueType[0] = resultValueType2[0];
+		resultValueType.set( resultValueType2.get() );
 		return result;
 	}
 
diff --git a/flatlaf-theme-editor/src/main/java/com/formdev/flatlaf/themeeditor/FlatThemePropertiesSupport.java b/flatlaf-theme-editor/src/main/java/com/formdev/flatlaf/themeeditor/FlatThemePropertiesSupport.java
index 0ce5345b..4a56736d 100644
--- a/flatlaf-theme-editor/src/main/java/com/formdev/flatlaf/themeeditor/FlatThemePropertiesSupport.java
+++ b/flatlaf-theme-editor/src/main/java/com/formdev/flatlaf/themeeditor/FlatThemePropertiesSupport.java
@@ -26,6 +26,7 @@ import java.util.HashSet;
 import java.util.Map;
 import java.util.Properties;
 import java.util.Set;
+import java.util.concurrent.atomic.AtomicReference;
 import java.util.function.Function;
 import javax.swing.UIDefaults;
 import javax.swing.event.DocumentEvent;
@@ -96,7 +97,7 @@ class FlatThemePropertiesSupport
 			return null;
 
 		try {
-			Object[] resultValueType = new Object[1];
+			AtomicReference<Object> resultValueType = new AtomicReference<>();
 			String value = resolveValue( keyValue.value );
 			parsedValue = UIDefaultsLoaderAccessor.parseValue( keyValue.key, value, resultValueType, resolver );
 			parsedValueCache.put( lineKey, parsedValue );
@@ -156,7 +157,7 @@ class FlatThemePropertiesSupport
 			return null;
 
 		try {
-			Object[] resultValueType = new Object[1];
+			AtomicReference<Object> resultValueType = new AtomicReference<>();
 			String value = resolveValue( str );
 			parsedValue = UIDefaultsLoaderAccessor.parseValue( key, value, resultValueType, resolver );
 			parsedValueCache2.put( key, parsedValue );