avoid worker restart unless it's slicing

js/kiri-work.js

@@ -39,6 +39,12 @@ if (self.window) {
     }
 
     KIRI.work = {
+        isSlicing : function() {
+            var current = 0;
+            for (var key in slicing) { current++ }
+            return current > 0;
+        },
+
         restart : function() {
             if (worker) worker.terminate();
 

js/kiri.js

@@ -2556,7 +2556,7 @@ self.kiri.license = exports.LICENSE;
                     // hide all dialogs
                     hideDialog();
                     // cancel slicing
-                    KIRI.work.restart();
+                    if (KIRI.work.isSlicing()) KIRI.work.restart();
                     break;
             }
             return false;

js/license.js

@@ -1,7 +1,7 @@
 var exports = {
     COPYRIGHT:"Copyright (C) 2014-2017 Stewart Allen <stewart@neuron.com> - All Rights Reserved",
     LICENSE:"Unauthorized copying, modification and re-distribution are strictly prohibited without prior written consent.",
-    VERSION:"1.2.0"
+    VERSION:"1.2.1"
 };
 if (!module) var module = {};
 module.exports = exports;