Copying/cutting a resource in Model Browser shows error message dialog due to invalid thread access

Caused by #74 (closed).

org.eclipse.swt.SWTException: Invalid thread access
	at org.eclipse.swt.SWT.error(SWT.java:4533)
	at org.eclipse.swt.SWT.error(SWT.java:4448)
	at org.eclipse.swt.SWT.error(SWT.java:4419)
	at org.eclipse.swt.widgets.Widget.error(Widget.java:482)
	at org.eclipse.swt.widgets.Widget.checkWidget(Widget.java:373)
	at org.eclipse.swt.widgets.Control.getForeground(Control.java:1400)
	at org.eclipse.jface.action.StatusLine.updateMessageLabel(StatusLine.java:687)
	at org.eclipse.jface.action.StatusLine.setMessage(StatusLine.java:565)
	at org.eclipse.jface.action.StatusLine.setMessage(StatusLine.java:551)
	at org.eclipse.jface.action.StatusLineManager.setMessage(StatusLineManager.java:239)
	at org.eclipse.jface.action.SubStatusLineManager.setMessage(SubStatusLineManager.java:103)
	at org.simantics.modeling.ui.modelBrowser.handlers.StandardCopyHandler.setStatus(StandardCopyHandler.java:163)
	at org.simantics.modeling.ui.modelBrowser.handlers.StandardCopyHandler.setCopyMessage(StandardCopyHandler.java:156)
	at org.simantics.modeling.ui.modelBrowser.handlers.StandardCopyHandler.copyResourcesToClipboard(StandardCopyHandler.java:144)
	at org.simantics.modeling.ui.modelBrowser.handlers.StandardCopyHandler$1.run(StandardCopyHandler.java:104)
	at org.eclipse.core.internal.jobs.Worker.run(Worker.java:56)