void HandleSplitterLineSegmentTreeLineRemoved (object sender, LineEventArgs e) { foreach (TextLineMarker marker in e.Line.Markers) { if (marker is IExtendingTextLineMarker) { lock (extendingTextMarkers) { HeightChanged = true; extendingTextMarkers.Remove (marker); } UnRegisterVirtualTextMarker ((IExtendingTextLineMarker)marker); } } }