OptionPane: fixed OptionPane.sameSizeButtons, which did not work as expected when setting to false

CHANGELOG.md

@@ -14,6 +14,8 @@ FlatLaf Change Log
   pressed) when running in Java 9+ on Linux, macOS. Occurs also on Windows in
   large popup menus that do not fit into the window. (issue #371; regression
   since FlatLaf 1.3)
+- OptionPane: Fixed `OptionPane.sameSizeButtons`, which did not work as expected
+  when setting to `false`.
 
 
 ## 1.5

flatlaf-core/src/main/java/com/formdev/flatlaf/ui/FlatOptionPaneUI.java

@@ -91,6 +91,7 @@ public class FlatOptionPaneUI
 	protected int messagePadding;
 	protected int maxCharactersPerLine;
 	private int focusWidth;
+	private boolean sameSizeButtons;
 
 	public static ComponentUI createUI( JComponent c ) {
 		return new FlatOptionPaneUI();
@@ -104,6 +105,7 @@ public class FlatOptionPaneUI
 		messagePadding = UIManager.getInt( "OptionPane.messagePadding" );
 		maxCharactersPerLine = UIManager.getInt( "OptionPane.maxCharactersPerLine" );
 		focusWidth = UIManager.getInt( "Component.focusWidth" );
+		sameSizeButtons = FlatUIUtils.getUIBoolean( "OptionPane.sameSizeButtons", true );
 	}
 
 	@Override
@@ -217,6 +219,11 @@ public class FlatOptionPaneUI
 		return null;
 	}
 
+	@Override
+	protected boolean getSizeButtonsToSameWidth() {
+		return sameSizeButtons;
+	}
+
 	//---- class NonUIResourceBorder ------------------------------------------
 
 	private static class NonUIResourceBorder