Describe the bug
When I'm starting Eclipse Platform Runtime from the latest I-build (I20260716-2300) on KDE with SWT_GTK4=1 GTK_THEME=Adwaita and try to create a new project, I see the following:
To Reproduce
Expected behavior
The menu should have these elements:

Screenshots
See above
Environment:
- Select the platform(s) on which the behavior is seen:
- 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
- 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
The problem doesn't appear without SWT_GTK4=1.
Logs:
WARNING: Using incubator modules: jdk.incubator.vector
Jul 17, 2026 3:37:34 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:53799): Gtk-CRITICAL **: 15:37:35.690: gtk_widget_get_next_sibling: assertion 'GTK_IS_WIDGET (widget)' failed
(Eclipse:53799): Gtk-CRITICAL **: 15:37:35.690: gtk_widget_unparent: assertion 'GTK_IS_WIDGET (widget)' failed
(Eclipse:53799): Gtk-WARNING **: 15:37:36.072: Trying to measure GtkLabel 0x7065415ea9f0 for height of 18, but it needs at least 19
(Eclipse:53799): Gtk-WARNING **: 15:37:43.912: gtk_widget_size_allocate(): attempt to allocate GtkImage image 0x7065425112f0 with width 16 and height -8
(Eclipse:53799): Gtk-WARNING **: 15:37:48.079: Trying to measure GtkSearchEntry 0x706542ace040 for width of 16, but it needs at least 73
(Eclipse:53799): Gtk-WARNING **: 15:37:48.079: Trying to measure GtkSearchEntry 0x706542ace040 for width of 16, but it needs at least 73
(Eclipse:53799): Gtk-WARNING **: 15:37:48.096: Trying to measure GtkSearchEntry 0x706542ace040 for width of 16, but it needs at least 73
(Eclipse:53799): Gtk-WARNING **: 15:37:48.096: Trying to measure GtkSearchEntry 0x706542ace040 for width of 16, but it needs at least 73
(Eclipse:53799): Gtk-WARNING **: 15:37:48.097: Trying to measure GtkLabel 0x704c38000bc0 for height of 18, but it needs at least 19
(Eclipse:53799): Gtk-CRITICAL **: 15:37:48.100: gtk_window_group_add_window: assertion 'GTK_IS_WINDOW (window)' failed
(Eclipse:53799): Gtk-WARNING **: 15:37:48.229: Trying to measure GtkSearchEntry 0x706542ace040 for width of 16, but it needs at least 73
(Eclipse:53799): Gtk-WARNING **: 15:37:48.229: Trying to measure GtkSearchEntry 0x706542ace040 for width of 16, but it needs at least 73
Then I clicked on Next > in the New Project dialog and the following logs appeared:
(Eclipse:53799): Gtk-WARNING **: 15:37:55.257: Trying to measure GtkEntry 0x70654228d0a0 for width of 16, but it needs at least 18
(Eclipse:53799): Gtk-WARNING **: 15:37:55.258: Trying to measure GtkEntry 0x70654228d0a0 for width of 16, but it needs at least 18
(Eclipse:53799): Gtk-WARNING **: 15:37:55.258: Trying to measure GtkEntry 0x706542cba7d0 for width of 16, but it needs at least 18
(Eclipse:53799): Gtk-WARNING **: 15:37:55.258: Trying to measure GtkEntry 0x706542cba7d0 for width of 16, but it needs at least 18
(Eclipse:53799): Gtk-WARNING **: 15:37:55.258: Trying to measure GtkCheckButton 0x70654054c900 for width of 90, but it needs at least 196
(Eclipse:53799): Gtk-WARNING **: 15:37:55.258: Trying to measure GtkEntry 0x70654228d0a0 for width of 16, but it needs at least 18
(Eclipse:53799): Gtk-WARNING **: 15:37:55.258: gtk_widget_size_allocate(): attempt to allocate GtkText text 0x70654038f290 with width -17 and height 26
(Eclipse:53799): Gtk-WARNING **: 15:37:55.258: Trying to measure GtkEntry 0x706542cba7d0 for width of 16, but it needs at least 18
(Eclipse:53799): Gtk-WARNING **: 15:37:55.258: gtk_widget_size_allocate(): attempt to allocate GtkText text 0x706541d3e0d0 with width -13 and height 26
(Eclipse:53799): Gtk-WARNING **: 15:37:55.258: gtk_widget_size_allocate(): attempt to allocate GtkBox box 0x7065424806c0 with width -9 and height 16
(Eclipse:53799): Gtk-WARNING **: 15:37:55.258: gtk_widget_size_allocate(): attempt to allocate GtkCellView cellview 0x706542d98610 with width -20 and height 0
(Eclipse:53799): Gtk-WARNING **: 15:37:55.271: Trying to measure GtkEntry 0x70654228d0a0 for width of 16, but it needs at least 18
(Eclipse:53799): Gtk-WARNING **: 15:37:55.271: Trying to measure GtkEntry 0x706542cba7d0 for width of 16, but it needs at least 18
Describe the bug
When I'm starting Eclipse Platform Runtime from the latest I-build (I20260716-2300) on KDE with
SWT_GTK4=1 GTK_THEME=Adwaitaand try to create a new project, I see the following:To Reproduce
Welcometab-Create a ProjectGeneral>ProjectExpected behavior

The menu should have these elements:
Screenshots
See above
Environment:
Version since
Workaround (or) Additional context
The problem doesn't appear without
SWT_GTK4=1.Logs:
Then I clicked on
Next >in theNew Projectdialog and the following logs appeared: