NPE in LaunchConfigurationTabGroupViewer.handleApplyPressed

[SougandhS]

While testing eclipse-jdt/eclipse.jdt.debug#909, I got this random NPE in LaunchConfigurationTabGroupViewer.handleApplyPressed when quickly toggling or switching between multiple launch configurations in the Launch Configurations dialog.

!ENTRY org.eclipse.jface 4 2 2026-03-14 06:34:02.590
!MESSAGE Problems occurred when invoking code from plug-in: "org.eclipse.jface".
!STACK 0
java.lang.NullPointerException: Cannot invoke "org.eclipse.debug.core.ILaunchConfiguration.getWorkingCopy()" because "this.fOriginal" is null
	at org.eclipse.debug.internal.ui.launchConfigurations.LaunchConfigurationTabGroupViewer.handleApplyPressed(LaunchConfigurationTabGroupViewer.java:1517)
	at org.eclipse.debug.internal.ui.launchConfigurations.LaunchConfigurationsDialog.handleLaunchConfigurationSelectionChanged(LaunchConfigurationsDialog.java:1033)
	at org.eclipse.debug.internal.ui.launchConfigurations.LaunchConfigurationsDialog.lambda$1(LaunchConfigurationsDialog.java:611)
	at org.eclipse.jface.viewers.StructuredViewer$3.run(StructuredViewer.java:822)
	at org.eclipse.core.runtime.SafeRunner.run(SafeRunner.java:47)
	at org.eclipse.jface.util.SafeRunnable.run(SafeRunnable.java:169)
	at org.eclipse.jface.viewers.StructuredViewer.firePostSelectionChanged(StructuredViewer.java:819)
	at org.eclipse.jface.viewers.ColumnViewer.firePostSelectionChanged(ColumnViewer.java:1054)
	at org.eclipse.jface.viewers.StructuredViewer.handlePostSelect(StructuredViewer.java:1188)
	at org.eclipse.swt.events.SelectionListener$1.widgetSelected(SelectionListener.java:83)
	at org.eclipse.jface.util.OpenStrategy.firePostSelectionEvent(OpenStrategy.java:283)
	at org.eclipse.jface.util.OpenStrategy$1.lambda$1(OpenStrategy.java:437)
	at org.eclipse.swt.widgets.RunnableLock.run(RunnableLock.java:40)
	at org.eclipse.swt.widgets.Synchronizer.runAsyncMessages(Synchronizer.java:132)
	at org.eclipse.swt.widgets.Display.runAsyncMessages(Display.java:4393)
	at org.eclipse.swt.widgets.Display.observerProc(Display.java:3929)
	at org.eclipse.swt.internal.cocoa.OS.objc_msgSendSuper(Native Method)
	at org.eclipse.swt.widgets.Display.applicationNextEventMatchingMask(Display.java:5589)
	at org.eclipse.swt.widgets.Display.applicationProc(Display.java:5990)
	at org.eclipse.swt.internal.cocoa.OS.objc_msgSendSuper(Native Method)
	at org.eclipse.swt.widgets.Widget.callSuper(Widget.java:239)
	at org.eclipse.swt.widgets.Widget.mouseDownSuper(Widget.java:1216)
	at org.eclipse.swt.widgets.Tree.mouseDownSuper(Tree.java:2190)
	at org.eclipse.swt.widgets.Widget.mouseDown(Widget.java:1208)
	at org.eclipse.swt.widgets.Control.mouseDown(Control.java:2598)
	at org.eclipse.swt.widgets.Tree.mouseDown(Tree.java:2157)
	at org.eclipse.swt.widgets.Display.windowProc(Display.java:6297)
	at org.eclipse.swt.internal.cocoa.OS.objc_msgSendSuper(Native Method)
	at org.eclipse.swt.widgets.Widget.callSuper(Widget.java:239)
	at org.eclipse.swt.widgets.Widget.windowSendEvent(Widget.java:2407)
	at org.eclipse.swt.widgets.Shell.windowSendEvent(Shell.java:2534)
	at org.eclipse.swt.widgets.Display.windowProc(Display.java:6413)
	at org.eclipse.swt.internal.cocoa.OS.objc_msgSendSuper(Native Method)
	at org.eclipse.swt.widgets.Display.applicationSendEvent(Display.java:5716)
	at org.eclipse.swt.widgets.Display.applicationProc(Display.java:5856)
	at org.eclipse.swt.internal.cocoa.OS.objc_msgSend(Native Method)
	at org.eclipse.swt.internal.cocoa.NSApplication.sendEvent(NSApplication.java:117)
	at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:4011)
	at org.eclipse.jface.window.Window.runEventLoop(Window.java:819)
	at org.eclipse.jface.window.Window.open(Window.java:799)
	at org.eclipse.debug.internal.ui.launchConfigurations.LaunchConfigurationsDialog.open(LaunchConfigurationsDialog.java:1238)
	at org.eclipse.debug.ui.DebugUITools.lambda$1(DebugUITools.java:631)
	at org.eclipse.swt.custom.BusyIndicator.showWhile(BusyIndicator.java:67)
	at org.eclipse.debug.ui.DebugUITools.openLaunchConfigurationDialogOnGroup(DebugUITools.java:637)
	at org.eclipse.debug.ui.DebugUITools.openLaunchConfigurationDialogOnGroup(DebugUITools.java:575)
	at org.eclipse.debug.ui.actions.OpenLaunchDialogAction.run(OpenLaunchDialogAction.java:85)
	at org.eclipse.jface.action.Action.runWithEvent(Action.java:474)
	at org.eclipse.jface.action.ActionContributionItem.handleWidgetSelection(ActionContributionItem.java:581)
	at org.eclipse.jface.action.ActionContributionItem.lambda$4(ActionContributionItem.java:415)
	at org.eclipse.swt.widgets.EventTable.sendEvent(EventTable.java:91)
	at org.eclipse.swt.widgets.Display.sendEvent(Display.java:4671)
	at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1657)
	at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1680)
	at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1665)
	at org.eclipse.swt.widgets.Widget.notifyListeners(Widget.java:1394)
	at org.eclipse.swt.widgets.Display.runDeferredEvents(Display.java:4438)
	at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:4014)
	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:185)
	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:104)
	at java.base/java.lang.reflect.Method.invoke(Method.java:565)
	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)