[GTK4] File > New dialog empty when using existing workspace

[danthe1st]

Describe the bug
When creating a workspace, closing Eclipse (I20260716-2300) and opening it again with SWT_GTK4=1 GTK_THEME=Adawaita, The File > New menu is empty

To Reproduce

• Download and extract Eclipse Platform Runtime binary (I20260716-2300) from https://download.eclipse.org/eclipse/downloads/drops4/I20260716-2300/
• Run it and create a new workspace
• Close the Welcome tab
• Close Eclipse
• Run it again with SWT_GTK4=1 GTK_THEME=Adawaita and open the workspace created earlier
• In the top menu, select File > New and the menu is empty

Expected behavior
The menu should show the normal entries. The following screenshot is with SWT_GTK4=1 GTK_THEME=Adawaita when creating a fresh workspace.

Screenshots
See above

Environment:

1. Select the platform(s) on which the behavior is seen:

• • All OS
• • Windows
• • Linux
• • macOS

2. Additional OS info (e.g. OS version, Linux Desktop, etc)

Operating System: Kubuntu 26.04 LTS
KDE Plasma Version: 6.6.5
KDE Frameworks Version: 6.24.0
Qt Version: 6.10.2
Kernel Version: 7.0.0-27-generic (64-bit)
Graphics Platform: Wayland
Processors: 8 × 11th Gen Intel® Core™ i5-1135G7 @ 2.40GHz
Memory: 16 GiB of RAM (14,9 GiB usable)
Graphics Processor: Intel® Iris® Xe Graphics
Manufacturer: HUAWEI
Product Name: KLVD-WXX9
System Version: M1260

3. JRE/JDK version

java version "25.0.2" 2026-01-20 LTS
Java(TM) SE Runtime Environment Oracle GraalVM 25.0.2+10.1 (build 25.0.2+10-LTS-jvmci-b01)
Java HotSpot(TM) 64-Bit Server VM Oracle GraalVM 25.0.2+10.1 (build 25.0.2+10-LTS-jvmci-b01, mixed mode, sharing)

Version since

*** System properties:
-Dorg.eclipse.swt.graphics.Resource.reportNonDisposed=true
-Dorg.eclipse.swt.graphics.Resource.reportNonDisposed=true
org.eclipse.swt.graphics.Resource.reportNonDisposed=true
org.eclipse.swt.internal.deviceZoom=100
org.eclipse.swt.internal.gdk.backend=wayland
org.eclipse.swt.internal.gtk.theme=Adwaita
org.eclipse.swt.internal.gtk.version=4.22.4
org.eclipse.swt.internal.webkitgtk.version=2.52.3
sun.java.command=/tmp/eclipse//plugins/org.eclipse.equinox.launcher_1.7.200.v20260619-2039.jar -os linux -ws gtk -arch x86_64 -showsplash -launcher /tmp/eclipse/eclipse -name Eclipse --launcher.library /tmp/eclipse//plugins/org.eclipse.equinox.launcher.gtk.linux.x86_64_1.2.1600.v20260613-0559/eclipse_11924.so -startup /tmp/eclipse//plugins/org.eclipse.equinox.launcher_1.7.200.v20260619-2039.jar --launcher.appendVmargs -exitdata 3b -vm /home/dan1st/.sdkman/candidates/java/current/bin/java -vmargs -Dosgi.requiredJavaVersion=21 -Dosgi.dataAreaRequiresExplicitInit=true -Dorg.eclipse.swt.graphics.Resource.reportNonDisposed=true -Dorg.slf4j.simpleLogger.defaultLogLevel=off -Declipse.platform.mergeTrust=true --add-modules=ALL-SYSTEM -jar /tmp/eclipse//plugins/org.eclipse.equinox.launcher_1.7.200.v20260619-2039.jar
swt.autoScale.updateOnRuntime=true

*** System environment variables:
SWT_GTK4=1

*** Features:

*** Plug-in Registry:
org.eclipse.e4.ui.css.swt (0.17.100.v20260706-1107) "Eclipse CSS SWT Support" [Active]
org.eclipse.e4.ui.css.swt.theme (0.15.200.v20260704-1645) "Eclipse CSS SWT Theme Support" [Active]
org.eclipse.e4.ui.workbench.addons.swt (1.6.100.v20260430-1313) "Eclipse e4 Workbench Add-ons" [Active]
org.eclipse.e4.ui.workbench.renderers.swt (0.18.100.v20260622-1026) "Eclipse e4 Workbench SWT Renderer" [Active]
org.eclipse.e4.ui.workbench.swt (0.18.200.v20260707-1437) "Eclipse e4 Workbench SWT" [Active]
org.eclipse.jface.databinding (1.16.0.v20251216-1230) "JFace Data Binding for SWT and JFace" [Resolved]
org.eclipse.swt (3.135.0.v20260716-1930) "Standard Widget Toolkit" [Resolved]
org.eclipse.swt.gtk.linux.x86_64 (3.135.0.v20260716-1930) "Standard Widget Toolkit for GTK on x86_64" [Resolved]
org.eclipse.swt.svg (3.133.100.v20260702-1546) "Standard Widget Toolkit for GTK on x86_64" [Resolved]

Workaround (or) Additional context
Not using GTK4 works.

Logs:

WARNING: Using incubator modules: jdk.incubator.vector
Jul 17, 2026 3:53:33 PM org.apache.aries.spifly.BaseActivator log
INFO: Registered provider org.slf4j.simple.SimpleServiceProvider of service org.slf4j.spi.SLF4JServiceProvider in bundle slf4j.simple

(Eclipse:73708): Gtk-CRITICAL **: 15:53:34.840: gtk_widget_get_next_sibling: assertion 'GTK_IS_WIDGET (widget)' failed

(Eclipse:73708): Gtk-CRITICAL **: 15:53:34.840: gtk_widget_unparent: assertion 'GTK_IS_WIDGET (widget)' failed

(Eclipse:73708): Gtk-WARNING **: 15:53:35.260: Trying to measure GtkLabel 0x710afd5f5990 for height of 18, but it needs at least 19

(Eclipse:73708): Gtk-WARNING **: 15:53:40.310: gtk_widget_size_allocate(): attempt to allocate GtkImage image 0x710afe5516b0 with width 16 and height -

The following logs are shown when closing Eclipse:

(Eclipse:73708): Gtk-CRITICAL **: 15:53:47.143: gtk_widget_unparent: assertion 'GTK_IS_WIDGET (widget)' failed

(Eclipse:73708): Gtk-CRITICAL **: 15:53:47.144: gtk_widget_unparent: assertion 'GTK_IS_WIDGET (widget)' failed

(Eclipse:73708): Gtk-CRITICAL **: 15:53:47.189: gtk_widget_unparent: assertion 'GTK_IS_WIDGET (widget)' failed