Ensure the JSpinners editor uses zero-size margins.

core/src/main/java/com/github/weisj/darklaf/ui/spinner/DarkSpinnerUI.java

@@ -30,6 +30,7 @@ import javax.swing.border.EmptyBorder;
 import javax.swing.plaf.ComponentUI;
 import javax.swing.plaf.UIResource;
 import javax.swing.plaf.basic.BasicSpinnerUI;
+import javax.swing.text.JTextComponent;
 
 import com.github.weisj.darklaf.components.ArrowButton;
 import com.github.weisj.darklaf.ui.DividedWidgetPainter;
@@ -145,6 +146,9 @@ public class DarkSpinnerUI extends BasicSpinnerUI implements SpinnerConstants {
         } else {
             editorComponent = editor;
         }
+        if (editorComponent instanceof JTextComponent) {
+            ((JTextComponent) editorComponent).setMargin(new Insets(0, 0, 0, 0));
+        }
         editorComponent.addFocusListener(spinnerListener);
     }