Test "javax/swing/JColorChooser/Test6977726.java" failed on ubuntu x64 because "Preview" title is missing for GTK L&F

OS:
Ubuntu

Environments:
Operating System: Ubuntu 24.04 LTS x64
Language: English
Processor: Intel® Xeon® Silver 4210 × 8
OS type: 64-bit
Memory: 18 GB
LAF: manual-laf-GTK-Dark

Reproducible: Always

Failed on Release/Build: JDK_23_b26
Is it a Regression in JDK 23 release: NO
[If Regression] Regression introduced in JDK 23 release/build: N/A
Test result on the last GAed release for this train: Failed on JDK_23_b24
Is it a platform-specific issue: Yes. This issue only happens on Linux.

General description of the problem:
The test case was displayed as expected but the user didn't see the title "Preview" as described.

Steps to reproduce:

     1. Run command:
#!/bin/sh -x
export JAVA_HOME=/home/ubuntu/Desktop/Reg_Client/jdk-23
export JT_HOME=/home/ubuntu/Desktop/Reg_Client/jtreg
export PATH=$PATH:$JAVA_HOME/bin:$JT_HOME/bin

jtreg \
-ignore:quiet \
-ea \
-esa \
-m \
-gui \
-vmoption:-Dswing.defaultlaf=com.sun.java.swing.plaf.gtk.GTKLookAndFeel \
-nativepath:/home/ubuntu/Desktop/Reg_Client/jdk-23-ea+26_linux-x64_bin-tests/jdk/jtreg/native \
-exclude:/home/ubuntu/Desktop/Reg_Client/open/test/jdk/ProblemList.txt \
-testjdk:/home/ubuntu/Desktop/Reg_Client/jdk-23 \
-dir:/home/ubuntu/Desktop/Reg_Client/open/test/jdk \
-reportDir:results/JTreport \
-workDir:results/JTwork \
-timeoutHandlerDir:/home/ubuntu/Desktop/Reg_Client/jdk-23-ea+26_linux-x64_bin-tests/failure_handler/jtregFailureHandler.jar \
-observerDir:/home/ubuntu/Desktop/Reg_Client/jdk-23-ea+26_linux-x64_bin-tests/failure_handler/jtregFailureHandler.jar \
-timeoutHandler:jdk.test.failurehandler.jtreg.GatherProcessInfoTimeoutHandler \
-observer:jdk.test.failurehandler.jtreg.GatherDiagnosticInfoObserver \
-timeoutHandlerTimeout:0 \
/home/ubuntu/Desktop/Reg_Client/open/test/jdk/:jdk_swing

      2. Run test case: javax/swing/JColorChooser/Test6977726.java
      3. Check and observe that there is a panel with "Text Preiview Panel" text and with title "Preview" in the JColorChooser

     Expected behavior:
The title "Preview" must be displayed in the panel as described.

     Actual behavior:
The user didn't see the title "Preview" as described

     Any non-default VM flags
/home/ubuntu/Desktop/Reg_Client/jdk-23/bin/java \\
        -Dtest.vm.opts='-ea -esa -Dswing.defaultlaf=com.sun.java.swing.plaf.gtk.GTKLookAndFeel' \\
        -Dtest.tool.vm.opts='-J-ea -J-esa -J-Dswing.defaultlaf=com.sun.java.swing.plaf.gtk.GTKLookAndFeel' \\
        -Dtest.compiler.opts= \\
        -Dtest.java.opts= \\
        -Dtest.jdk=/home/ubuntu/Desktop/Reg_Client/jdk-23 \\
        -Dcompile.jdk=/home/ubuntu/Desktop/Reg_Client/jdk-23 \\
        -Dtest.timeout.factor=1.0 \\
        -Dtest.nativepath=/home/ubuntu/Desktop/Reg_Client/jdk-23-ea+26_linux-x64_bin-tests/jdk/jtreg/native \\
        -Dtest.root=/home/ubuntu/Desktop/Reg_Client/open/test/jdk \\
        -Dtest.name=javax/swing/JColorChooser/Test6977726.java \\
        -Dtest.file=/home/ubuntu/Desktop/Reg_Client/open/test/jdk/javax/swing/JColorChooser/Test6977726.java \\
        -Dtest.src=/home/ubuntu/Desktop/Reg_Client/open/test/jdk/javax/swing/JColorChooser \\
        -Dtest.src.path=/home/ubuntu/Desktop/Reg_Client/open/test/jdk/javax/swing/JColorChooser:/home/ubuntu/Desktop/Reg_Client/open/test/jdk/java/awt/regtesthelpers \\
        -Dtest.classes=/home/ubuntu/Desktop/Reg_Client/results/JTwork/classes/javax/swing/JColorChooser/Test6977726.d \\
        -Dtest.class.path=/home/ubuntu/Desktop/Reg_Client/results/JTwork/classes/javax/swing/JColorChooser/Test6977726.d:/home/ubuntu/Desktop/Reg_Client/results/JTwork/classes/java/awt/regtesthelpers \\
        -Dtest.modules=java.desktop \\
        --add-modules java.desktop \\
        -ea \\
        -esa \\
        -Dswing.defaultlaf=com.sun.java.swing.plaf.gtk.GTKLookAndFeel \\
        -Djava.library.path=/home/ubuntu/Desktop/Reg_Client/jdk-23-ea+26_linux-x64_bin-tests/jdk/jtreg/native \\
        com.sun.javatest.regtest.agent.MainWrapper /home/ubuntu/Desktop/Reg_Client/results/JTwork/javax/swing/JColorChooser/Test6977726.d/main.0.jta