diff --git a/test/jdk/javax/swing/JComboBox/bug4139900.java b/test/jdk/javax/swing/JComboBox/bug4139900.java
new file mode 100644
index 00000000000..a9ed685d5ab
--- /dev/null
+++ b/test/jdk/javax/swing/JComboBox/bug4139900.java
@@ -0,0 +1,119 @@
+/*
+ * Copyright (c) 1999, 2025, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+/*
+ * @test
+ * @bug 4139900
+ * @summary height of combobox may differ
+ * @key headful
+ * @run main bug4139900
+*/
+
+import java.awt.Dimension;
+import java.awt.Robot;
+import java.awt.event.ActionListener;
+import javax.swing.DefaultComboBoxModel;
+import javax.swing.JButton;
+import javax.swing.JComboBox;
+import javax.swing.JFrame;
+import javax.swing.JPanel;
+import javax.swing.SwingUtilities;
+
+public class bug4139900 {
+    static JButton button;
+    static JFrame frame;
+    static JComboBox<String> comboBox;
+    static int initialHeight;
+
+    public static void main(String[] args) throws Exception {
+        try {
+            SwingUtilities.invokeAndWait(bug4139900::init);
+            test();
+        } finally {
+            SwingUtilities.invokeAndWait(() -> {
+                if (frame != null) {
+                    frame.dispose();
+                }
+            });
+        }
+    }
+
+    private static void test() throws Exception {
+        Robot robot = new Robot();
+        robot.waitForIdle();
+        robot.delay(500);
+
+        SwingUtilities.invokeAndWait(() -> initialHeight = comboBox.getHeight());
+
+        for (int i = 0; i < 10; i++) {
+            SwingUtilities.invokeAndWait(() -> button.doClick());
+            robot.waitForIdle();
+            robot.delay(200);
+            SwingUtilities.invokeAndWait(() -> {
+                if (comboBox.getHeight() != initialHeight) {
+                    throw new RuntimeException(
+                            "Test failed: height differs from initial %d != %d"
+                                    .formatted(comboBox.getHeight(), initialHeight)
+                    );
+                }
+            });
+        }
+    }
+
+    public static void init() {
+        frame = new JFrame("bug4139900");
+
+        DefaultComboBoxModel<String> model =
+                new DefaultComboBoxModel<>(new String[]{
+                        "Coma Berenices",
+                        "Triangulum",
+                        "Camelopardis",
+                        "Cassiopea"
+                });
+
+        comboBox = new JComboBox<>();
+        comboBox.setEditable(true);
+
+        button = new JButton("Add/Remove Items");
+
+        ActionListener actionListener = e -> {
+            if (comboBox.getModel() == model) {
+                comboBox.setModel(new DefaultComboBoxModel<>());
+            } else {
+                comboBox.setModel(model);
+            }
+        };
+
+        button.addActionListener(actionListener);
+
+        JPanel panel = new JPanel();
+        panel.setPreferredSize(new Dimension(300, 100));
+        panel.add(comboBox);
+        panel.add(button);
+
+        frame.add(panel);
+        frame.pack();
+        frame.setLocationRelativeTo(null);
+        frame.setVisible(true);
+    }
+}
diff --git a/test/jdk/javax/swing/JComboBox/bug4174876.java b/test/jdk/javax/swing/JComboBox/bug4174876.java
new file mode 100644
index 00000000000..349dfa4b159
--- /dev/null
+++ b/test/jdk/javax/swing/JComboBox/bug4174876.java
@@ -0,0 +1,78 @@
+/*
+ * Copyright (c) 1999, 2025, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+/*
+ * @test
+ * @bug 4174876
+ * @summary JComboBox tooltips do not work properly
+ * @library /java/awt/regtesthelpers
+ * @build PassFailJFrame
+ * @run main/manual bug4174876
+ */
+
+import javax.swing.JComboBox;
+import javax.swing.JComponent;
+import javax.swing.JPanel;
+
+public class bug4174876 {
+    private static final String INSTRUCTIONS = """
+            Hold the mouse over both combo boxes.
+            A tool tip should appear over every area of both of them.
+            Notably, if you hold the mouse over the button on the right one,
+            a tool tip should appear.
+            """;
+
+    public static void main(String[] args) throws Exception {
+        PassFailJFrame.builder()
+                .title("TransparentTitleTest Instructions")
+                .instructions(INSTRUCTIONS)
+                .columns(40)
+                .splitUIBottom(bug4174876::createTestUI)
+                .build()
+                .awaitAndCheck();
+    }
+
+    private static JComponent createTestUI() {
+        JComboBox<String> comboBox1 = new JComboBox<>(new String[]{
+                "Coma Berenices",
+                "Triangulum",
+                "Camelopardis",
+                "Cassiopea"
+        });
+        JComboBox<String> comboBox2 = new JComboBox<>(new String[]{
+                "Coma Berenices",
+                "Triangulum",
+                "Camelopardis",
+                "Cassiopea"
+        });
+
+        comboBox1.setToolTipText("Combo Box #1");
+        comboBox2.setToolTipText("Combo Box #2");
+        comboBox2.setEditable(true);
+
+        JPanel panel = new JPanel();
+        panel.add(comboBox1);
+        panel.add(comboBox2);
+        return panel;
+    }
+}
diff --git a/test/jdk/javax/swing/JComboBox/bug4474400.java b/test/jdk/javax/swing/JComboBox/bug4474400.java
new file mode 100644
index 00000000000..ea52d0c71b5
--- /dev/null
+++ b/test/jdk/javax/swing/JComboBox/bug4474400.java
@@ -0,0 +1,78 @@
+/*
+ * Copyright (c) 2001, 2025, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+/*
+ * @test
+ * @bug 4474400
+ * @summary Tests JTextArea wrapping with font change
+ * @library /java/awt/regtesthelpers
+ * @build PassFailJFrame
+ * @run main/manual bug4474400
+ */
+
+import java.awt.BorderLayout;
+import java.awt.Dimension;
+import java.awt.Font;
+import javax.swing.JButton;
+import javax.swing.JComponent;
+import javax.swing.JPanel;
+import javax.swing.JTextArea;
+
+public class bug4474400 {
+    private static final String INSTRUCTIONS = """
+            Press the "Change Font" button. The two lines of text should be
+            properly drawn using the larger font, there should be empty line
+            between them. If display is garbled, test fails.
+            """;
+
+    public static void main(String[] args) throws Exception {
+        PassFailJFrame.builder()
+                .title("bug4474400 Instructions")
+                .instructions(INSTRUCTIONS)
+                .columns(40)
+                .splitUIRight(bug4474400::createTestUI)
+                .build()
+                .awaitAndCheck();
+    }
+
+    private static JComponent createTestUI() {
+        Font smallFont = new Font("SansSerif", Font.PLAIN, 12);
+        Font largeFont = new Font("SansSerif", Font.PLAIN, 36);
+
+        JTextArea textArea = new JTextArea("This is the first line\n\nThis is the third line");
+        textArea.setFont(smallFont);
+        textArea.setEditable(false);
+        textArea.setLineWrap(true);
+        textArea.setWrapStyleWord(true);
+
+        JButton b = new JButton("Change Font");
+        b.addActionListener((e) -> textArea.setFont(largeFont));
+
+        JPanel panel = new JPanel(new BorderLayout());
+        panel.setPreferredSize(new Dimension(200, 300));
+        panel.add(textArea, BorderLayout.CENTER);
+        panel.add(b, BorderLayout.SOUTH);
+
+        return panel;
+    }
+}
diff --git a/test/jdk/javax/swing/border/TransparentTitleTest.java b/test/jdk/javax/swing/border/TransparentTitleTest.java
new file mode 100644
index 00000000000..49a32a5890c
--- /dev/null
+++ b/test/jdk/javax/swing/border/TransparentTitleTest.java
@@ -0,0 +1,122 @@
+/*
+ * Copyright (c) 1999, 2025, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+/*
+ * @test
+ * @bug 4154572
+ * @summary Tests that the area behind a TitledBorder's title string is transparent,
+ * allowing the component's background to show through
+ * @library /java/awt/regtesthelpers
+ * @build PassFailJFrame
+ * @run main/manual TransparentTitleTest
+ */
+
+import java.awt.GridLayout;
+import java.awt.Dimension;
+import java.awt.Graphics;
+import java.awt.Color;
+import java.awt.image.BufferedImage;
+import javax.swing.ImageIcon;
+import javax.swing.JFrame;
+import javax.swing.JPanel;
+import javax.swing.border.TitledBorder;
+import javax.swing.border.LineBorder;
+
+public class TransparentTitleTest {
+    private static final String INSTRUCTIONS = """
+            If all panels are correctly painted such that the title of the
+            border allows the underlying panel image (green rectangle)
+            to show through the background of the text,
+            then this test passes; else it fails.
+            """;
+
+    public static void main(String[] args) throws Exception {
+        PassFailJFrame.builder()
+                .title("TransparentTitleTest Instructions")
+                .instructions(INSTRUCTIONS)
+                .columns(40)
+                .testUI(TransparentTitleTest::createTestUI)
+                .build()
+                .awaitAndCheck();
+    }
+
+    private static JFrame createTestUI() {
+        JFrame frame = new JFrame("TransparentTitleTest");
+
+        frame.setLayout(new GridLayout(3, 6, 5, 5));
+
+        frame.add(new ImagePanel(TitledBorder.TOP, TitledBorder.LEFT));
+        frame.add(new ImagePanel(TitledBorder.TOP, TitledBorder.CENTER));
+        frame.add(new ImagePanel(TitledBorder.TOP, TitledBorder.RIGHT));
+        frame.add(new ImagePanel(TitledBorder.ABOVE_TOP, TitledBorder.LEFT));
+        frame.add(new ImagePanel(TitledBorder.ABOVE_TOP, TitledBorder.CENTER));
+        frame.add(new ImagePanel(TitledBorder.ABOVE_TOP, TitledBorder.RIGHT));
+        frame.add(new ImagePanel(TitledBorder.BELOW_TOP, TitledBorder.LEFT));
+        frame.add(new ImagePanel(TitledBorder.BELOW_TOP, TitledBorder.CENTER));
+        frame.add(new ImagePanel(TitledBorder.BELOW_TOP, TitledBorder.RIGHT));
+        frame.add(new ImagePanel(TitledBorder.BOTTOM, TitledBorder.LEFT));
+        frame.add(new ImagePanel(TitledBorder.BOTTOM, TitledBorder.CENTER));
+        frame.add(new ImagePanel(TitledBorder.BOTTOM, TitledBorder.RIGHT));
+        frame.add(new ImagePanel(TitledBorder.ABOVE_BOTTOM, TitledBorder.LEFT));
+        frame.add(new ImagePanel(TitledBorder.ABOVE_BOTTOM, TitledBorder.CENTER));
+        frame.add(new ImagePanel(TitledBorder.ABOVE_BOTTOM, TitledBorder.RIGHT));
+        frame.add(new ImagePanel(TitledBorder.BELOW_BOTTOM, TitledBorder.LEFT));
+        frame.add(new ImagePanel(TitledBorder.BELOW_BOTTOM, TitledBorder.CENTER));
+        frame.add(new ImagePanel(TitledBorder.BELOW_BOTTOM, TitledBorder.RIGHT));
+
+        frame.pack();
+        return frame;
+    }
+}
+
+class ImagePanel extends JPanel {
+
+    private final ImageIcon imageIcon;
+
+    private static final BufferedImage bufferedImage =
+            new BufferedImage(128, 128, BufferedImage.TYPE_INT_ARGB);
+
+    static {
+        Graphics g = bufferedImage.getGraphics();
+        g.setColor(Color.GREEN);
+        g.fillRect(0, 0, 128, 128);
+    }
+
+    public ImagePanel(int titlePos, int titleJust) {
+        imageIcon = new ImageIcon(bufferedImage);
+
+        TitledBorder b = new TitledBorder(new LineBorder(Color.black,3), "title text");
+        b.setTitlePosition(titlePos);
+        b.setTitleJustification(titleJust);
+        b.setTitleColor(Color.black);
+        setBorder(b);
+    }
+
+    public Dimension getPreferredSize() {
+        return new Dimension(imageIcon.getIconWidth(), imageIcon.getIconHeight());
+    }
+
+    public void paintComponent(Graphics g) {
+        imageIcon.paintIcon(this, g, 0, 0);
+    }
+}