"Invalid thread access" in DoNothingMainTab

[jukzi]

it's only an example code... but even examples should work

org.eclipse.swt.SWTException: Invalid thread access
	at org.eclipse.swt.SWT.error(SWT.java:4918)
	at org.eclipse.swt.SWT.error(SWT.java:4833)
	at org.eclipse.swt.SWT.error(SWT.java:4804)
	at org.eclipse.swt.widgets.Widget.error(Widget.java:450)
	at org.eclipse.swt.widgets.Widget.checkWidget(Widget.java:370)
	at org.eclipse.swt.widgets.Button.getSelection(Button.java:623)
	at org.eclipse.debug.internal.examples.mixedmode.DoNothingMainTab.launchConfigurationChanged(DoNothingMainTab.java:117)
	at org.eclipse.debug.internal.core.LaunchManager$ConfigurationNotifier.run(LaunchManager.java:225)
	at org.eclipse.core.runtime.SafeRunner.run(SafeRunner.java:45)
	at org.eclipse.debug.internal.core.LaunchManager$ConfigurationNotifier.notify(LaunchManager.java:209)
	at org.eclipse.debug.internal.core.LaunchManager.launchConfigurationChanged(LaunchManager.java:2148)
	at org.eclipse.debug.internal.core.LaunchConfigurationWorkingCopy.writeNewFile(LaunchConfigurationWorkingCopy.java:377)
	at org.eclipse.debug.internal.core.LaunchConfigurationWorkingCopy.doSave0(LaunchConfigurationWorkingCopy.java:259)
	at org.eclipse.core.internal.resources.Workspace.run(Workspace.java:2380)
	at org.eclipse.core.internal.resources.Workspace.run(Workspace.java:2405)
	at org.eclipse.debug.internal.core.LaunchConfigurationWorkingCopy.doSave(LaunchConfigurationWorkingCopy.java:226)
	at org.eclipse.debug.internal.ui.launchConfigurations.LaunchConfigurationTabGroupViewer.lambda$6(LaunchConfigurationTabGroupViewer.java:1509)
	at org.eclipse.jface.operation.ModalContext$ModalContextThread.run(ModalContext.java:122)