Dark theme errors on Eclipse 2026-06

[mwensveen-ebpi]

I installed Eclipse 2026-06 on Ubuntu with wayland.
Started eclipse in a new workspace
Installed DevStyle from the eclipse market place

As suggested by DevStyle I did
export WEBKIT_DISABLE_COMPOSITING_MODE=1
before starting eclipse.

On the views all tabs are gone (see screenshot).

In the log there are errors
If I switch to a default eclipse theme it looks alright.

eclipse.log

[alessandro-fardin]

Same problem here, but I'm using ubuntu 2022.04 with X11

[kongra]

• Eclipse version: 2026-06 (jee)
  • Plugin version: 2025.2.0.202509301431
  • Error: Cannot invoke "java.lang.reflect.Field.setAccessible(boolean)" because "this.lastTabHeight" is null on startup
  • OS: Linuxmint 22.3

[gtjoseph]

Same issue with Fedora 44 XFCE (X11)

[amadeuheredia]

Same issue here. Attached log:

java.lang.NullPointerException: Cannot invoke "java.lang.reflect.Field.setAccessible(boolean)" because "this.lastTabHeight" is null
	at com.genuitec.eclipse.theming.ui.rendering.SquareTabRenderer$CTabFolderRendererWrapper.resetCurves(SquareTabRenderer.java:669)
	at com.genuitec.eclipse.theming.ui.rendering.SquareTabRenderer.computeSize(SquareTabRenderer.java:159)
	at org.eclipse.swt.custom.CTabFolder.setItemSize(CTabFolder.java:2923)
	at org.eclipse.swt.custom.CTabFolder.updateItems(CTabFolder.java:3933)
	at org.eclipse.swt.custom.CTabFolder.updateItems(CTabFolder.java:3866)
	at org.eclipse.swt.custom.CTabFolder.onResize(CTabFolder.java:2148)
	at org.eclipse.swt.custom.CTabFolder.lambda$0(CTabFolder.java:339)
	at org.eclipse.swt.widgets.EventTable.sendEvent(EventTable.java:91)
	at org.eclipse.swt.widgets.Display.sendEvent(Display.java:5865)
	at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1656)
	at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1682)
	at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1661)
	at org.eclipse.swt.widgets.Control.setBounds(Control.java:1235)
	at org.eclipse.swt.widgets.Composite.setBounds(Composite.java:1702)
	at org.eclipse.swt.widgets.Control.setBounds(Control.java:1003)
	at org.eclipse.e4.ui.workbench.renderers.swt.SashLayout.setRectangle(SashLayout.java:321)
	at org.eclipse.e4.ui.workbench.renderers.swt.SashLayout.tileSubNodes(SashLayout.java:269)
	at org.eclipse.e4.ui.workbench.renderers.swt.SashLayout.tileSubNodes(SashLayout.java:313)
	at org.eclipse.e4.ui.workbench.renderers.swt.SashLayout.tileSubNodes(SashLayout.java:313)
	at org.eclipse.e4.ui.workbench.renderers.swt.SashLayout.tileSubNodes(SashLayout.java:313)
	at org.eclipse.e4.ui.workbench.renderers.swt.SashLayout.tileSubNodes(SashLayout.java:313)
	at org.eclipse.e4.ui.workbench.renderers.swt.SashLayout.layout(SashLayout.java:179)
	at org.eclipse.swt.widgets.Composite.updateLayout(Composite.java:1913)
	at org.eclipse.swt.widgets.Composite.setBounds(Composite.java:1705)
	at org.eclipse.swt.widgets.Control.setBounds(Control.java:1043)
	at org.eclipse.swt.layout.FillLayout.layout(FillLayout.java:216)
	at org.eclipse.swt.widgets.Composite.updateLayout(Composite.java:1913)
	at org.eclipse.swt.widgets.Composite.setBounds(Composite.java:1705)
	at org.eclipse.swt.widgets.Control.setBounds(Control.java:1003)
	at org.eclipse.swt.custom.StackLayout.layout(StackLayout.java:124)
	at org.eclipse.swt.widgets.Composite.updateLayout(Composite.java:1913)
	at org.eclipse.swt.widgets.Composite.setBounds(Composite.java:1705)
	at org.eclipse.swt.widgets.Control.setBounds(Control.java:1003)
	at org.eclipse.e4.ui.workbench.renderers.swt.SashLayout.setRectangle(SashLayout.java:321)
	at org.eclipse.e4.ui.workbench.renderers.swt.SashLayout.tileSubNodes(SashLayout.java:269)
	at org.eclipse.e4.ui.workbench.renderers.swt.SashLayout.tileSubNodes(SashLayout.java:313)
	at org.eclipse.e4.ui.workbench.renderers.swt.SashLayout.layout(SashLayout.java:179)
	at org.eclipse.swt.widgets.Composite.updateLayout(Composite.java:1913)
	at org.eclipse.swt.widgets.Composite.setBounds(Composite.java:1705)
	at org.eclipse.swt.widgets.Control.setBounds(Control.java:1043)
	at org.eclipse.swt.layout.FillLayout.layout(FillLayout.java:216)
	at org.eclipse.swt.widgets.Composite.updateLayout(Composite.java:1913)
	at org.eclipse.swt.widgets.Composite.setBounds(Composite.java:1705)
	at org.eclipse.swt.widgets.Control.setBounds(Control.java:1003)
	at org.eclipse.e4.ui.workbench.renderers.swt.TrimmedPartLayout.layout(TrimmedPartLayout.java:177)
	at org.eclipse.swt.widgets.Composite.updateLayout(Composite.java:1913)
	at org.eclipse.swt.widgets.Composite.layout(Composite.java:1363)
	at org.eclipse.swt.widgets.Control.requestLayout(Control.java:4599)
	at org.eclipse.jface.action.ToolBarManager.relayout(ToolBarManager.java:229)
	at org.eclipse.jface.action.ToolBarManager.update(ToolBarManager.java:394)
	at org.eclipse.e4.ui.workbench.renderers.swt.ToolBarManagerRenderer.updateWidget(ToolBarManagerRenderer.java:736)
	at org.eclipse.e4.ui.workbench.renderers.swt.ToolBarManagerRenderer.subscribeUIElementTopicVisible(ToolBarManagerRenderer.java:220)
	at java.base/jdk.internal.reflect.DirectMethodHandleAccessor.invoke(DirectMethodHandleAccessor.java:103)
	at java.base/java.lang.reflect.Method.invoke(Method.java:580)
	at org.eclipse.e4.core.internal.di.MethodRequestor.execute(MethodRequestor.java:58)
	at org.eclipse.swt.widgets.Synchronizer.syncExec(Synchronizer.java:182)
	at org.eclipse.ui.internal.UISynchronizer.syncExec(UISynchronizer.java:136)
	at org.eclipse.swt.widgets.Display.syncExec(Display.java:5970)
	at org.eclipse.e4.ui.workbench.swt.DisplayUISynchronize.syncExec(DisplayUISynchronize.java:34)
	at org.eclipse.e4.ui.internal.di.UIEventObjectSupplier$UIEventHandler.handleEvent(UIEventObjectSupplier.java:65)
	at org.eclipse.equinox.internal.event.EventHandlerWrapper.handleEvent(EventHandlerWrapper.java:206)
	at org.eclipse.equinox.internal.event.EventHandlerTracker.dispatchEvent(EventHandlerTracker.java:201)
	at org.eclipse.equinox.internal.event.EventHandlerTracker.dispatchEvent(EventHandlerTracker.java:1)
	at org.eclipse.osgi.framework.eventmgr.EventManager.dispatchEvent(EventManager.java:230)
	at org.eclipse.osgi.framework.eventmgr.ListenerQueue.dispatchEventSynchronous(ListenerQueue.java:151)
	at org.eclipse.equinox.internal.event.EventAdminImpl.dispatchEvent(EventAdminImpl.java:132)
	at org.eclipse.equinox.internal.event.EventAdminImpl.sendEvent(EventAdminImpl.java:73)
	at org.eclipse.equinox.internal.event.EventComponent.sendEvent(EventComponent.java:48)
	at org.eclipse.e4.ui.services.internal.events.EventBroker.send(EventBroker.java:55)
	at org.eclipse.e4.ui.internal.workbench.UIEventPublisher.notifyChanged(UIEventPublisher.java:61)
	at org.eclipse.emf.common.notify.impl.BasicNotifierImpl.eNotify(BasicNotifierImpl.java:424)
	at org.eclipse.e4.ui.model.application.ui.impl.UIElementImpl.setVisible(UIElementImpl.java:365)
	at org.eclipse.e4.ui.workbench.renderers.swt.ToolBarManagerRenderer$3.changed(ToolBarManagerRenderer.java:679)
	at org.eclipse.e4.core.internal.contexts.TrackableComputationExt.update(TrackableComputationExt.java:109)
	at org.eclipse.e4.core.internal.contexts.EclipseContext.processScheduled(EclipseContext.java:371)
	at org.eclipse.e4.core.internal.contexts.EclipseContext.set(EclipseContext.java:387)
	at org.eclipse.ui.internal.services.EvaluationService.requestEvaluation(EvaluationService.java:262)
	at org.eclipse.oomph.internal.ui.UIPropertyTester$3.run(UIPropertyTester.java:97)
	at org.eclipse.oomph.ui.UIUtil.syncExec(UIUtil.java:634)
	at org.eclipse.oomph.internal.ui.UIPropertyTester.requestEvaluation(UIPropertyTester.java:84)
	at org.eclipse.oomph.setup.ui.SetupPropertyTester.setPerformingShell(SetupPropertyTester.java:266)
	at org.eclipse.oomph.setup.ui.wizards.ProgressPage$12$1$1.run(ProgressPage.java:734)
	at org.eclipse.oomph.ui.UIUtil$7.run(UIUtil.java:695)
	at org.eclipse.ui.internal.PendingSyncExec.run(PendingSyncExec.java:68)
	at org.eclipse.ui.internal.UILockListener.doPendingWork(UILockListener.java:166)
	at org.eclipse.swt.widgets.RunnableLock.run(RunnableLock.java:40)
	at org.eclipse.swt.widgets.Synchronizer.runAsyncMessages(Synchronizer.java:131)
	at org.eclipse.swt.widgets.Display.runAsyncMessages(Display.java:5055)
	at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:4518)
	at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine$5.run(PartRenderingEngine.java:1160)
	at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:339)
	at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.run(PartRenderingEngine.java:1051)
	at org.eclipse.e4.ui.internal.workbench.E4Workbench.createAndRunUI(E4Workbench.java:153)
	at org.eclipse.ui.internal.Workbench.lambda$3(Workbench.java:684)
	at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:339)
	at org.eclipse.ui.internal.Workbench.createAndRunWorkbench(Workbench.java:583)
	at org.eclipse.ui.PlatformUI.createAndRunWorkbench(PlatformUI.java:173)
	at org.eclipse.ui.internal.ide.application.IDEApplication.start(IDEApplication.java:193)
	at org.eclipse.equinox.internal.app.EclipseAppHandle.run(EclipseAppHandle.java:219)
	at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.runApplication(EclipseAppLauncher.java:149)
	at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.start(EclipseAppLauncher.java:115)
	at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:467)
	at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:298)
	at java.base/jdk.internal.reflect.DirectMethodHandleAccessor.invoke(DirectMethodHandleAccessor.java:103)
	at java.base/java.lang.reflect.Method.invoke(Method.java:580)
	at org.eclipse.equinox.launcher.Main.invokeFramework(Main.java:615)
	at org.eclipse.equinox.launcher.Main.basicRun(Main.java:563)
	at org.eclipse.equinox.launcher.Main.run(Main.java:1415)
	at org.eclipse.equinox.launcher.Main.main(Main.java:1387)

[brianvfernandes]

Hey everyone - we've escalated this to the CodeTogether team; they're aware of the issue and are investigating.

[RoiSoleil]

Could you please implement testing on the current development version of Eclipse to prevent the Darkest Dark plugin from having errors in the final release of Eclipse ? This plugin is widely used in the community (thanks for that!), and this doesn't reflect well on Eclipse overall. ;)

[souravdas142]

followups

[KRM1234]

Hello togeher,
same issue on Windows11 with Eclipse 2026-06.
'layouting editor' has encountered a problem.
Details:
An internal error has occurred.
Cannot invoke "java.lang.reflect.Field.setAccessible(boolean)" because "this.lastTabHeight" is null

KR
Marcus

[gtjoseph]

@brianvfernandes Any progress on this issue?

[Shadows-of-Fire]

Given the lack of updates I've put together a patcher for this issue https://github.com/Shadows-of-Fire/revstyle

Though I don't know how many eclipse updates into the future will be patchable. DevStyle reaches into eclipse internals quite a bit (that's why it crashes in the first place)