because safari/webkit is fundamentally braindead

app.js

@@ -728,7 +728,10 @@ function minify(path) {
         return code;
     }
     let mini = uglify.minify(code.toString(), {
-        compress: { unused: false }
+        compress: {
+            merge_vars: false,
+            unused: false
+        }
     });
     if (mini.error) {
         console.trace(mini.error);

src/kiri-mode/cam/prepare.js

@@ -26,9 +26,8 @@ const POLY = polygons;
  * @param {Number} [index] into widget array
  * @param {Object} [firstPoint] starting point
  */
-CAM.prepare = async function(widgets, settings, update) {
-    widgets = widgets.filter(w => !w.track.ignore && !w.meta.disabled);
-
+CAM.prepare = async function(widall, settings, update) {
+    const widgets = widall.filter(w => !w.track.ignore && !w.meta.disabled);
     const count = widgets.length;
     const weight = 1/count;
     const print = self.worker.print = kiri.newPrint(settings, widgets);