diff --git a/bin/jmeter.properties b/bin/jmeter.properties
index bac04e85bc9..a5446b45d05 100644
--- a/bin/jmeter.properties
+++ b/bin/jmeter.properties
@@ -1182,11 +1182,14 @@ cookies=cookies
 #jsyntaxtextarea.wrapstyleword=true
 #jsyntaxtextarea.linewrap=true
 #jsyntaxtextarea.codefolding=true
+#jsyntaxtextarea.highlight=true
 # Set 0 to disable undo feature in JSyntaxTextArea
 #jsyntaxtextarea.maxundos=50
 # Change the font on the (JSyntax) Text Areas. (Useful for HiDPI screens)
 #jsyntaxtextarea.font.family=Hack
 #jsyntaxtextarea.font.size=14
+#jsyntaxtextarea.theme.default=themes/default.xml
+#jsyntaxtextarea.theme.dark=themes/dark.xml
 
 # Set this to false to disable the use of JSyntaxTextArea for the Console Logger panel
 #loggerpanel.usejsyntaxtext=true
diff --git a/src/bom-thirdparty/build.gradle.kts b/src/bom-thirdparty/build.gradle.kts
index 6d54246c2b1..f4976b91f75 100644
--- a/src/bom-thirdparty/build.gradle.kts
+++ b/src/bom-thirdparty/build.gradle.kts
@@ -45,7 +45,7 @@ dependencies {
         api("com.fasterxml.jackson.core:jackson-annotations:2.16.1")
         api("com.fasterxml.jackson.core:jackson-core:2.16.1")
         api("com.fasterxml.jackson.core:jackson-databind:2.16.1")
-        api("com.fifesoft:rsyntaxtextarea:3.3.4")
+        api("com.fifesoft:rsyntaxtextarea:3.6.0")
         api("com.formdev:svgSalamander:1.1.4")
         api("com.github.ben-manes.caffeine:caffeine:2.9.3")
         api("com.github.weisj:darklaf-core:2.7.3")
@@ -143,5 +143,17 @@ dependencies {
         api("xerces:xercesImpl:2.12.2")
         api("xml-apis:xml-apis:1.4.01")
         api("xmlpull:xmlpull:1.1.3.1")
+        //FlatLaf: https://www.formdev.com/flatlaf/native-libraries/#gradle
+        val flatlafVersion = "3.6.2"
+        api("com.formdev:flatlaf:${flatlafVersion}" )
+        api("com.formdev:flatlaf:${flatlafVersion}:linux-x86_64@so")
+        api("com.formdev:flatlaf:${flatlafVersion}:macos-x86_64@dylib")
+        api("com.formdev:flatlaf:${flatlafVersion}:windows-x86_64@dll")
+        api("com.formdev:flatlaf-intellij-themes:${flatlafVersion}")
+        api("com.formdev:flatlaf-extras:${flatlafVersion}")
+        api("com.formdev:flatlaf-fonts-inter:4.1")
+        api("com.formdev:flatlaf-fonts-jetbrains-mono:2.304")
+        api("com.formdev:flatlaf-fonts-roboto:2.137")
+        api("com.formdev:flatlaf-fonts-roboto-mono:3.000")
     }
 }
diff --git a/src/core/build.gradle.kts b/src/core/build.gradle.kts
index 98160b953a5..c8ad78b4197 100644
--- a/src/core/build.gradle.kts
+++ b/src/core/build.gradle.kts
@@ -132,6 +132,9 @@ dependencies {
     testFixturesApi(testFixtures(projects.src.jorphan))
     testFixturesImplementation(projects.src.testkit)
     testFixturesImplementation("org.junit.jupiter:junit-jupiter")
+
+    implementation( "com.formdev:flatlaf" )
+    implementation( "com.formdev:flatlaf-intellij-themes" )
 }
 
 val generatedVersionDir = layout.buildDirectory.dir("generated/sources/version")
diff --git a/src/core/src/main/java/org/apache/jmeter/SplashScreen.java b/src/core/src/main/java/org/apache/jmeter/SplashScreen.java
index b3326bb221b..ff5851ee0e9 100644
--- a/src/core/src/main/java/org/apache/jmeter/SplashScreen.java
+++ b/src/core/src/main/java/org/apache/jmeter/SplashScreen.java
@@ -30,6 +30,7 @@
 import javax.swing.SwingUtilities;
 import javax.swing.border.EmptyBorder;
 
+import org.apache.jmeter.gui.action.LookAndFeelCommand;
 import org.apache.jmeter.util.JMeterUtils;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
@@ -74,7 +75,7 @@ public static JComponent loadLogo() {
             log.warn("Unable to find logo {}", svgResourcePath, e);
         }
 
-        if (svgUri != null) {
+        if (svgUri != null && LookAndFeelCommand.isDarklafTheme()) {
             Icon icon = new ThemedSVGIcon(svgUri, 521, 177);
             logo.setIcon(icon);
         } else {
diff --git a/src/core/src/main/java/org/apache/jmeter/gui/LoggerPanel.java b/src/core/src/main/java/org/apache/jmeter/gui/LoggerPanel.java
index 6e380a7f8ce..1017ba5a754 100644
--- a/src/core/src/main/java/org/apache/jmeter/gui/LoggerPanel.java
+++ b/src/core/src/main/java/org/apache/jmeter/gui/LoggerPanel.java
@@ -83,7 +83,7 @@ private JTextArea init() { // WARNING: called from ctor so must not be overridde
             JSyntaxTextArea jSyntaxTextArea = JSyntaxTextArea.getInstance(15, 80, true);
             jSyntaxTextArea.setSyntaxEditingStyle(SyntaxConstants.SYNTAX_STYLE_NONE);
             jSyntaxTextArea.setCodeFoldingEnabled(false);
-            jSyntaxTextArea.setAntiAliasingEnabled(false);
+            jSyntaxTextArea.setAntiAliasingEnabled(true);
             jSyntaxTextArea.setEditable(false);
             jSyntaxTextArea.setLineWrap(false);
             jSyntaxTextArea.setLanguage("text");
diff --git a/src/core/src/main/java/org/apache/jmeter/gui/MainFrame.java b/src/core/src/main/java/org/apache/jmeter/gui/MainFrame.java
index 969bed78c3b..42c5ddc8d03 100644
--- a/src/core/src/main/java/org/apache/jmeter/gui/MainFrame.java
+++ b/src/core/src/main/java/org/apache/jmeter/gui/MainFrame.java
@@ -247,7 +247,7 @@ public MainFrame(TreeModel treeModel, JMeterTreeListener treeListener) {
             // Shift down means "horizontal scrolling" on macOS, and we need only vertical one
             if ((e.getModifiersEx() & (ctrlAltMask | InputEvent.SHIFT_DOWN_MASK)) == ctrlAltMask) {
                 e.consume();
-                final float scale = 1.1f;
+                final float scale = JMeterUtils.getPropDefault("zoom_scale", 1.1f);
                 int rotation = e.getWheelRotation();
                 if (rotation > 0) { // DOWN
                     JMeterUtils.applyScaleOnFonts(1.0f / scale);
@@ -642,7 +642,7 @@ private static JScrollPane createMainPanel() {
     private static LoggerPanel createLoggerPanel() {
         LoggerPanel loggerPanel = new LoggerPanel();
         loggerPanel.setMinimumSize(new Dimension(0, 100));
-        loggerPanel.setPreferredSize(new Dimension(0, 150));
+        loggerPanel.setPreferredSize(new Dimension(0, 100));
         GuiPackage guiInstance = GuiPackage.getInstance();
         guiInstance.setLoggerPanel(loggerPanel);
         guiInstance.getMenuItemLoggerPanel().getModel().setSelected(DISPLAY_LOGGER_PANEL);
diff --git a/src/core/src/main/java/org/apache/jmeter/gui/action/LookAndFeelCommand.java b/src/core/src/main/java/org/apache/jmeter/gui/action/LookAndFeelCommand.java
index 0821b8a05d3..d6ff93abe6c 100644
--- a/src/core/src/main/java/org/apache/jmeter/gui/action/LookAndFeelCommand.java
+++ b/src/core/src/main/java/org/apache/jmeter/gui/action/LookAndFeelCommand.java
@@ -36,9 +36,12 @@
 import org.apache.jmeter.gui.util.JMeterMenuBar;
 import org.apache.jmeter.util.JMeterUtils;
 import org.apache.jorphan.gui.JFactory;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
+import com.formdev.flatlaf.FlatLaf;
+import com.formdev.flatlaf.intellijthemes.FlatAllIJThemes;
 import com.github.weisj.darklaf.LafManager;
-import com.github.weisj.darklaf.theme.DarculaTheme;
 import com.github.weisj.darklaf.theme.Theme;
 import com.google.auto.service.AutoService;
 
@@ -47,6 +50,7 @@
  */
 @AutoService(Command.class)
 public class LookAndFeelCommand extends AbstractAction {
+    private static final Logger log = LoggerFactory.getLogger(LookAndFeelCommand.class);
     private static final String JMETER_LAF = "jmeter.laf"; // $NON-NLS-1$
 
     private static final Map<String, MenuItem> items = new LinkedHashMap<>();
@@ -106,11 +110,29 @@ private static MenuItem ofDarklafTheme(Theme theme) {
         if (System.getProperty("darklaf.treeRowPopup") == null) {
             System.setProperty("darklaf.treeRowPopup", "false");
         }
-        UIManager.installLookAndFeel(JMeterMenuBar.DARCULA_LAF, JMeterMenuBar.DARCULA_LAF_CLASS);
+
+        //Add FlatLAF Themes
+        for (String flatLaf : new String[]{"FlatLightLaf", "FlatDarkLaf", "FlatIntelliJLaf", "FlatDarculaLaf"}) {
+            try {
+                UIManager.installLookAndFeel(flatLaf, "com.formdev.flatlaf." + flatLaf);
+            } catch( Exception ex ) {
+                log.warn("Failed to load FlatLAF theme: {}", flatLaf, ex);
+            }
+        }
+        for (String flatLaf : new String[]{"FlatMacDarkLaf", "FlatMacLightLaf"}) {
+            try {
+                UIManager.installLookAndFeel(flatLaf, "com.formdev.flatlaf.themes" + flatLaf);
+            } catch( Exception ex ) {
+                log.warn("Failed to load FlatLAF theme: {}", flatLaf, ex);
+            }
+        }
+        for (UIManager.LookAndFeelInfo lafInfo : FlatAllIJThemes.INFOS) {
+            UIManager.installLookAndFeel(lafInfo.getName(), lafInfo.getClassName());
+        }
 
         List<MenuItem> items = new ArrayList<>();
         for (UIManager.LookAndFeelInfo laf : JMeterMenuBar.getAllLAFs()) {
-            if (!laf.getClassName().equals(JMeterMenuBar.DARCULA_LAF_CLASS)) {
+            if (!laf.getClassName().equals(JMeterMenuBar.DARKLAF_LAF_CLASS)) {
                 items.add(MenuItem.of(laf.getName(), laf.getClassName()));
             } else {
                 for (Theme theme : LafManager.getRegisteredThemes()) {
@@ -143,15 +165,10 @@ public static Collection<MenuItem> getMenuItems() {
      */
     @Deprecated
     public static String getJMeterLaf(){
-        String laf = PREFS.get(USER_PREFS_KEY, null);
-        if (laf != null) {
-            return checkLafName(laf);
-        }
-
         String osName = System.getProperty("os.name") // $NON-NLS-1$
                         .toLowerCase(Locale.ENGLISH);
         // Spaces are not allowed in property names read from files
-        laf = JMeterUtils.getProperty(JMETER_LAF+"."+osName.replace(' ', '_'));
+        String laf = JMeterUtils.getProperty(JMETER_LAF+"."+osName.replace(' ', '_'));
         if (laf != null) {
             return checkLafName(laf);
         }
@@ -160,10 +177,7 @@ public static String getJMeterLaf(){
         if (laf != null) {
             return checkLafName(laf);
         }
-        laf = JMeterUtils.getPropDefault(JMETER_LAF, JMeterMenuBar.DARCULA_LAF_CLASS);
-        if (laf != null) {
-            return checkLafName(laf);
-        }
+
         return UIManager.getCrossPlatformLookAndFeelClassName();
     }
 
@@ -174,16 +188,16 @@ public static String getJMeterLaf(){
     public static String getPreferredLafCommand() {
         String laf = PREFS.get(USER_PREFS_KEY, null);
         if (laf != null) {
-            return laf;
+            MenuItem item = items.get(laf);
+            if (item == null) {
+                log.warn("LookAndFeel command '{}' not found in available items, falling back to default LAFs", laf);
+            } else {
+                return item.command;
+            }
         }
 
         String jMeterLaf = getJMeterLaf();
-        if (jMeterLaf.equals(JMeterMenuBar.DARCULA_LAF_CLASS)) {
-            // Convert old Darcula to new Darklaf-Darcula LaF
-            return MenuItem.ofDarklafTheme(new DarculaTheme()).command;
-        }
-
-        return MenuItem.of("default", jMeterLaf).command; // $NON-NLS-1$
+            return MenuItem.of("default", jMeterLaf).command; // $NON-NLS-1$
     }
 
     // Check if LAF is a built-in one
@@ -205,8 +219,12 @@ public static boolean isDarklafTheme() {
         return "Darklaf".equalsIgnoreCase(UIManager.getLookAndFeel().getID()); // $NON-NLS-1$
     }
 
+    public static boolean isFlatlafTheme() {
+        return UIManager.getLookAndFeel() instanceof FlatLaf;
+    }
+
     public static boolean isDark() {
-        return isDarklafTheme() && Theme.isDark(LafManager.getTheme());
+        return (isDarklafTheme() && Theme.isDark(LafManager.getTheme())) || (isFlatlafTheme() && ((FlatLaf)UIManager.getLookAndFeel()).isDark());
     }
 
     public static void activateLookAndFeel(String command) {
diff --git a/src/core/src/main/java/org/apache/jmeter/gui/util/JMeterMenuBar.java b/src/core/src/main/java/org/apache/jmeter/gui/util/JMeterMenuBar.java
index 4f829e9d2ea..3ec22f2e9ba 100644
--- a/src/core/src/main/java/org/apache/jmeter/gui/util/JMeterMenuBar.java
+++ b/src/core/src/main/java/org/apache/jmeter/gui/util/JMeterMenuBar.java
@@ -53,6 +53,7 @@
 import org.apache.jmeter.util.LocaleChangeEvent;
 import org.apache.jmeter.util.LocaleChangeListener;
 import org.apache.jmeter.util.SSLManager;
+import org.apache.jorphan.gui.GuiUtils;
 import org.apache.jorphan.reflect.LogAndIgnoreServiceLoadExceptionHandler;
 import org.apache.jorphan.util.JOrphanUtils;
 import org.apache.logging.log4j.Level;
@@ -101,10 +102,10 @@ public class JMeterMenuBar extends JMenuBar implements LocaleChangeListener {
 
     public static final String SYSTEM_LAF = "System"; // $NON-NLS-1$
     public static final String CROSS_PLATFORM_LAF = "CrossPlatform"; // $NON-NLS-1$
-    public static final String DARCULA_LAF = "Darcula"; // $NON-NLS-1$
     public static final String DARKLAF_LAF = "Darklaf"; // $NON-NLS-1$
-    public static final String DARCULA_LAF_CLASS = "com.bulenkov.darcula.DarculaLaf"; // $NON-NLS-1$
+    public static final String FLAT_LAF = "FlatLaf"; // $NON-NLS-1$
     public static final String DARKLAF_LAF_CLASS = "com.github.weisj.darklaf.DarkLaf"; // $NON-NLS-1$
+    public static final String FLATLAF_LAF_CLASS = "com.formdev.flatlaf.FlatLightLaf"; // $NON-NLS-1$
 
     public JMeterMenuBar() {
         // List for recent files menu items
@@ -317,6 +318,7 @@ private void makeOptionsMenu() {
 
     private static JMenu createLaFMenu() {
         JMenu lafMenu = makeMenuRes("appearance", 'L');
+        JMenu flatLafSubMenu = new JMenu("FlatLaf Themes");
         ButtonGroup lafGroup = new ButtonGroup();
         String currentLafCommand = LookAndFeelCommand.getPreferredLafCommand();
         for (LookAndFeelCommand.MenuItem item : LookAndFeelCommand.getMenuItems()) {
@@ -326,9 +328,16 @@ private static JMenu createLaFMenu() {
             if (item.getCommand().equals(currentLafCommand)) {
                 menuItem.setSelected(true);
             }
+            if (item.getCommand().startsWith("laf:com.formdev.flatlaf")) {
+                flatLafSubMenu.add(menuItem);
+            } else {
+                lafMenu.add(menuItem);
+            }
             lafGroup.add(menuItem);
-            lafMenu.add(menuItem);
         }
+        GuiUtils.makeScrollableMenu(flatLafSubMenu);
+        lafMenu.addSeparator();
+        lafMenu.add(flatLafSubMenu);
         return lafMenu;
     }
 
diff --git a/src/core/src/main/java/org/apache/jmeter/gui/util/JSyntaxTextArea.java b/src/core/src/main/java/org/apache/jmeter/gui/util/JSyntaxTextArea.java
index 6625fa75777..ba1196ed2e5 100644
--- a/src/core/src/main/java/org/apache/jmeter/gui/util/JSyntaxTextArea.java
+++ b/src/core/src/main/java/org/apache/jmeter/gui/util/JSyntaxTextArea.java
@@ -29,13 +29,16 @@
 import javax.swing.SwingUtilities;
 import javax.swing.UIManager;
 
+import org.apache.commons.lang3.StringUtils;
 import org.apache.jmeter.gui.action.LookAndFeelCommand;
 import org.apache.jmeter.util.JMeterUtils;
 import org.apache.jorphan.gui.JFactory;
 import org.apache.jorphan.gui.JMeterUIDefaults;
 import org.apache.jorphan.gui.ui.TextComponentUI;
 import org.fife.ui.rsyntaxtextarea.RSyntaxTextArea;
+import org.fife.ui.rsyntaxtextarea.Style;
 import org.fife.ui.rsyntaxtextarea.SyntaxConstants;
+import org.fife.ui.rsyntaxtextarea.SyntaxScheme;
 import org.fife.ui.rsyntaxtextarea.Theme;
 import org.fife.ui.rtextarea.RUndoManager;
 import org.slf4j.Logger;
@@ -53,7 +56,8 @@ public class JSyntaxTextArea extends RSyntaxTextArea {
     private static final long serialVersionUID = 211L;
     private static final Logger log = LoggerFactory.getLogger(JSyntaxTextArea.class);
 
-    private static final Theme DEFAULT_THEME = loadTheme(Theme.class, "themes/default.xml");
+    private static final Theme DEFAULT_THEME = loadTheme(Theme.class, JMeterUtils.getPropDefault("jsyntaxtextarea.theme.default", "themes/default.xml"));
+    private static final Theme DEFAULT_DARK_THEME = loadTheme(Theme.class, JMeterUtils.getPropDefault("jsyntaxtextarea.theme.dark", "themes/dark.xml"));
 
     private final Properties languageProperties = JMeterUtils.loadProperties("org/apache/jmeter/gui/util/textarea.properties"); //$NON-NLS-1$
 
@@ -64,6 +68,7 @@ public class JSyntaxTextArea extends RSyntaxTextArea {
     private static final int MAX_UNDOS = JMeterUtils.getPropDefault("jsyntaxtextarea.maxundos", 50);
     private static final String USER_FONT_FAMILY = JMeterUtils.getPropDefault("jsyntaxtextarea.font.family", null);
     private static final int USER_FONT_SIZE = JMeterUtils.getPropDefault("jsyntaxtextarea.font.size", -1);
+    private static final boolean HIGHLIGHT_OCCURRENCES = JMeterUtils.getPropDefault("jsyntaxtextarea.highlight", true);
 
     private static final HierarchyListener GUTTER_THEME_PATCHER = e -> {
         if ((e.getChangeFlags() & HierarchyEvent.PARENT_CHANGED) != 0
@@ -93,6 +98,7 @@ public class JSyntaxTextArea extends RSyntaxTextArea {
     public static JSyntaxTextArea getInstance(int rows, int cols, boolean disableUndo) {
         try {
             JSyntaxTextArea jSyntaxTextArea = new JSyntaxTextArea(rows, cols, disableUndo);
+            jSyntaxTextArea.createPopupMenu();
             JFactory.withDynamic(jSyntaxTextArea, JSyntaxTextArea::applyTheme);
             // Gutter styling is only applied if the text area is contained in a scroll pane.
             jSyntaxTextArea.addHierarchyListener(GUTTER_THEME_PATCHER);
@@ -143,16 +149,53 @@ public String getText() {
      */
     private static void applyTheme(JSyntaxTextArea jSyntaxTextArea) {
         final boolean isDarklafTheme = LookAndFeelCommand.isDarklafTheme();
-        final Theme theme = isDarklafTheme ? new DarklafRSyntaxTheme(jSyntaxTextArea) : DEFAULT_THEME;
+        final boolean isFlatlafTheme = LookAndFeelCommand.isFlatlafTheme();
+        final Theme theme = isDarklafTheme ? new DarklafRSyntaxTheme(jSyntaxTextArea) : (LookAndFeelCommand.isDark() ? DEFAULT_DARK_THEME : DEFAULT_THEME);
+
+        // Calculate scaled font size
+        float scale = JMeterUIDefaults.INSTANCE.getScale();
+        Font baseFont;
+        if (USER_FONT_FAMILY != null) {
+            baseFont = JMeterUIDefaults.createFont(USER_FONT_FAMILY, Font.PLAIN, USER_FONT_SIZE > 0 ? USER_FONT_SIZE : 12);
+        } else {
+            baseFont = jSyntaxTextArea.getFont();
+        }
+        if (Math.abs(scale - 1.0f) > 0.01) {
+            baseFont = baseFont.deriveFont(baseFont.getSize2D() * scale);
+        }
+
+        // Apply theme first
         if (theme != null) {
             theme.apply(jSyntaxTextArea);
-            Font font = jSyntaxTextArea.getFont();
-            float scale = JMeterUIDefaults.INSTANCE.getScale();
-            if (Math.abs(scale - 1.0f) > 0.01) {
-                font = font.deriveFont(font.getSize2D() * scale);
-                jSyntaxTextArea.setFont(font);
+        }
+
+        // Apply scaled font to all token types
+        SyntaxScheme scheme = jSyntaxTextArea.getSyntaxScheme();
+        for (int i = 0; i < scheme.getStyleCount(); i++) {
+            Style style = scheme.getStyle(i);
+            if (style != null) {
+                if (style.font != null) {
+                    // Keep the style (bold/italic) but use scaled size
+                    style.font = style.font.deriveFont(baseFont.getSize2D());
+                } else {
+                    style.font = baseFont;
+                }
             }
         }
+        jSyntaxTextArea.setFont(baseFont);
+        jSyntaxTextArea.setSyntaxScheme(scheme);
+        jSyntaxTextArea.setFractionalFontMetricsEnabled(true);
+
+        if (isFlatlafTheme) {
+            jSyntaxTextArea.setForeground(UIManager.getColor("TextArea.foreground"));
+            jSyntaxTextArea.setCaretColor(UIManager.getColor("TextArea.caretForeground"));
+            jSyntaxTextArea.setSelectionColor(UIManager.getColor("TextArea.selectionBackground"));
+            jSyntaxTextArea.setSelectedTextColor(UIManager.getColor("TextArea.selectionForeground"));
+            if (UIManager.getColor("Hyperlink.linkColor") != null) {
+                jSyntaxTextArea.setHyperlinkForeground(UIManager.getColor("Hyperlink.linkColor"));
+        }
+            }
+
         if (!isDarklafTheme) {
             // Darklaf themes provide a custom background color for editors, so we don't overwrite it.
             Color color = UIManager.getColor("TextArea.background");
@@ -241,14 +284,31 @@ public JSyntaxTextArea(int rows, int cols, boolean disableUndo) {
         super.setAntiAliasingEnabled(true);
         super.setLineWrap(LINE_WRAP);
         super.setWrapStyleWord(WRAP_STYLE_WORD);
+        super.setMarkOccurrences(HIGHLIGHT_OCCURRENCES);
         this.disableUndo = disableUndo;
+
+        // Add component listener to handle window resizing
+        addComponentListener(new java.awt.event.ComponentAdapter() {
+            @Override
+            public void componentResized(java.awt.event.ComponentEvent e) {
+                // Ensure text wraps to the new width
+                revalidate();
+                repaint();
+            }
+        });
+
+        int fontSize = USER_FONT_SIZE > 0 ? USER_FONT_SIZE : getFont().getSize();
+        Font font = getFont();
         if (USER_FONT_FAMILY != null) {
-            int fontSize = USER_FONT_SIZE > 0 ? USER_FONT_SIZE : getFont().getSize();
-            setFont(JMeterUIDefaults.createFont(USER_FONT_FAMILY, Font.PLAIN, fontSize));
+            font = JMeterUIDefaults.createFont(USER_FONT_FAMILY, Font.PLAIN, fontSize);
+        } else {
+            font = font.deriveFont(font.getStyle(), fontSize);
+        }
+        setFont(font);
             if (log.isDebugEnabled()) {
                 log.debug("Font is set to: {}", getFont());
             }
-        }
+
         if(disableUndo) {
             TextComponentUI.uninstallUndo(this);
             // We need to do this to force recreation of undoManager which
diff --git a/src/core/src/main/java/org/apache/jmeter/gui/util/TextAreaCellRenderer.java b/src/core/src/main/java/org/apache/jmeter/gui/util/TextAreaCellRenderer.java
index cb8600a5d80..5e8131f98b6 100644
--- a/src/core/src/main/java/org/apache/jmeter/gui/util/TextAreaCellRenderer.java
+++ b/src/core/src/main/java/org/apache/jmeter/gui/util/TextAreaCellRenderer.java
@@ -21,8 +21,11 @@
 import java.awt.Component;
 
 import javax.swing.JTable;
+import javax.swing.UIManager;
 import javax.swing.table.TableCellRenderer;
 
+import org.apache.jmeter.gui.action.LookAndFeelCommand;
+
 public class TextAreaCellRenderer implements TableCellRenderer {
 
     private JSyntaxTextArea rend = createRenderer(""); //$NON-NLS-1$
@@ -36,13 +39,20 @@ public Component getTableCellRendererComponent(JTable table, Object value,
         } else {
             rend = createRenderer(""); //$NON-NLS-1$
         }
+
         if (hasFocus || isSelected) {
-            rend.setBackground(Color.blue);
+            if (LookAndFeelCommand.isFlatlafTheme()) {
+                rend.setBackground(UIManager.getColor("Table.selectionBackground"));
+                rend.setForeground(UIManager.getColor("Table.selectionForeground"));
+            } else {
+                rend.setBackground(Color.pink);
             rend.setForeground(Color.white);
         }
+        }
         if (table.getRowHeight(row) < getPreferredHeight()) {
             table.setRowHeight(row, getPreferredHeight());
         }
+
         return JTextScrollPane.getInstance(rend);
     }
 
diff --git a/src/jorphan/src/main/java/org/apache/jorphan/gui/JMeterUIDefaults.java b/src/jorphan/src/main/java/org/apache/jorphan/gui/JMeterUIDefaults.java
index b8e98da783a..8605dc14973 100644
--- a/src/jorphan/src/main/java/org/apache/jorphan/gui/JMeterUIDefaults.java
+++ b/src/jorphan/src/main/java/org/apache/jorphan/gui/JMeterUIDefaults.java
@@ -103,11 +103,13 @@ private JMeterUIDefaults() {
     @API(since = "5.3", status = API.Status.INTERNAL)
     public void install() {
         DynamicStyle.onLaFChange(() -> {
+            log.info("LAF changed, updating JMeter-specific properties"); // $NON-NLS-1$
             // We put JMeter-specific properties into getLookAndFeelDefaults,
             // so the properties are removed when LaF is changed
             UIDefaults defaults = UIManager.getLookAndFeelDefaults();
 
             if (Math.abs(scale - 1.0f) > 0.01f) {
+                log.info("Applying scale factor: {}", scale); // $NON-NLS-1$
                 scaleFonts(defaults);
                 scaleIntProperties(defaults, scale);
                 // We don't want to make controls extra big, so we damp the scaling factors
@@ -183,8 +185,9 @@ private static void configureRowHeight(UIDefaults defaults, float scale, String
             if (f == null) {
                 height = 16 * scale;
             } else {
-                Canvas c = new Canvas();
-                height = c.getFontMetrics(f).getHeight();
+                //Canvas c = new Canvas();
+                //height = c.getFontMetrics(f).getHeight();
+                height = f.getSize2D();
             }
             // Set line height to be 1.3 of the font size. The number of completely made up,
             // 1.2 seems to be the minimal usable scale. 1.3 looks good.
diff --git a/xdocs/stylesheets/website-style.xsl b/xdocs/stylesheets/website-style.xsl
index 9b8dbddae96..e826bdf2796 100644
--- a/xdocs/stylesheets/website-style.xsl
+++ b/xdocs/stylesheets/website-style.xsl
@@ -38,7 +38,7 @@
   <xsl:param name="cssdir" select="concat($relative-path, '/css')" />
   <xsl:param name="apidir" select="concat($relative-path, '/api')" />
   <xsl:param name="jakarta-site" select="'https://jakarta.apache.org'" />
-  <xsl:param name="year" select="'2024'" />
+  <xsl:param name="year" select="'2025'" />
   <xsl:param name="max-img-width" select="'600'" />
 
   <!-- Output method -->
diff --git a/xdocs/usermanual/properties_reference.xml b/xdocs/usermanual/properties_reference.xml
index d74ece0613d..df5fb25b29d 100644
--- a/xdocs/usermanual/properties_reference.xml
+++ b/xdocs/usermanual/properties_reference.xml
@@ -1507,6 +1507,10 @@ JMETER-SERVER</source>
     Set to zero to disable undo feature in JSyntaxTextArea.<br/>
     Defaults to: <code>50</code>
 </property>
+  <property name="jsyntaxtextarea.highlight">
+    Set to false to disable word highlight in JSyntaxTextArea.<br/>
+    Defaults to: <code>true</code>
+  </property>
 <property name="jsyntaxtextarea.font.family">
     Change the font on the (JSyntax) Text Areas. (Useful for HiDPI screens).<br/>
     Defaults to empty value, which means platform default monospaced font
@@ -1515,6 +1519,13 @@ JMETER-SERVER</source>
     Change the size of the (JSyntax) Text Areas. Will be used only,
     when <code>jsyntaxtextarea.font.family</code> is set.<br/>
     Defaults to: <code>-1</code></property>
+  <property name="jsyntaxtextarea.theme.default">
+    Change the default theme of the (JSyntax) Text Areas.<br/>
+    Defaults to: <code>themes/default.xml</code></property>
+  <property name="jsyntaxtextarea.theme.dark">
+    Change the default dark theme of the (JSyntax) Text Areas. When LAF is
+    detected to be of 'dark' type this is also applied in (JSyntax) Text Areas.<br/>
+    Defaults to: <code>themes/dark.xml</code></property>
 <property name="loggerpanel.usejsyntaxtext">
     Set this to <code>false</code> to disable the use of JSyntaxTextArea
     for the Console Logger panel.<br/>