clear can only be done pre-slice, not during filter synth

src/kiri/main.js

@@ -871,6 +871,9 @@
         setOpacity(color.slicing_opacity);
 
         STACKS.clear();
+        if (mode === 'FDM') {
+            KIRI.client.clear();
+        }
         KIRI.client.sync();
         KIRI.client.rotate(settings);
 

src/mode/fdm/client.js

@@ -22,19 +22,13 @@
         SPACE = api.const.SPACE;
 
         function filterSynth() {
-            // remove synth widgets
-            let clear = false;
             api.widgets.filter((widget) => {
                 if (widget.track.synth) {
                     api.const.SPACE.platform.remove(widget.mesh);
                     kiri.Widget.Groups.remove(widget);
-                    clear = true;
                 }
                 return !widget.track.synth
             });
-            if (clear) {
-                kiri.client.clear();
-            }
         }
 
         api.event.on("mode.set", mode => {