if (!(viewer instanceof ISourceViewerExtension2))
return; // cannot unconfigure - do nothing
// XXX: this is pretty heavy-weight
((ISourceViewerExtension2)viewer).unconfigure();
viewer.configure(getSourceViewerConfiguration());
if (Boolean.FALSE.equals(event.getNewValue()))
SpellingProblem.removeAllInActiveEditor(this, null);
IAction quickAssistAction= getAction(ITextEditorActionConstants.QUICK_ASSIST);