Ignore invalid tool

src/main/java/com/plotsquared/bukkit/listeners/worldedit/WESubscriber.java

@@ -72,11 +72,14 @@ public class WESubscriber {
                         Player objPlayer = ((BukkitPlayer) player).player;
                         ItemStack item = objPlayer.getItemInHand();
                         if (item != null && !hasMask) {
+                            try {
                                 BrushTool tool = session.getBrushTool(item.getTypeId());
                                 if (tool != null) {
                                     hasMask = tool.getMask() != null;
                                 }
                             }
+                            catch (Exception e) {}
+                        }
                         AbstractDelegateExtent extent = (AbstractDelegateExtent) event.getExtent();
                         ChangeSetExtent history = null;
                         MultiStageReorder reorder = null;