diff --git a/js/common/NaturalSelectionQueryParameters.js b/js/common/NaturalSelectionQueryParameters.js
index 3b630745..a8153d7f 100644
--- a/js/common/NaturalSelectionQueryParameters.js
+++ b/js/common/NaturalSelectionQueryParameters.js
@@ -213,7 +213,7 @@ const SCHEMA = {
   // Tuned in https://github.com/phetsims/natural-selection/issues/86
   shortTeethMultiplier: {
     type: 'number',
-    defaultValue: 2 ,
+    defaultValue: 2,
     isValidValue: value => ( value > 1 )
   },
 
diff --git a/js/common/view/FastForwardButton.js b/js/common/view/FastForwardButton.js
index 042f72cf..046b34e7 100644
--- a/js/common/view/FastForwardButton.js
+++ b/js/common/view/FastForwardButton.js
@@ -26,8 +26,8 @@ class FastForwardButton extends RoundMomentaryButton {
 
     options = merge( {
       radius: 16,
-      xMargin:8,
-      yMargin:8,
+      xMargin: 8,
+      yMargin: 8,
 
       // phet-io
       tandem: Tandem.REQUIRED
diff --git a/js/common/view/PlayButtonGroup.js b/js/common/view/PlayButtonGroup.js
index eca19c7f..bf57cf58 100644
--- a/js/common/view/PlayButtonGroup.js
+++ b/js/common/view/PlayButtonGroup.js
@@ -78,25 +78,25 @@ class PlayButtonGroup extends Node {
     // Make at most 1 button visible. unlink is not necessary.
     simulationModeProperty.link( simulationMode => {
 
-      // start with all buttons hidden
-      addAMateButton.visible = false;
-      playButton.visible = false;
-      startOverButton.visible = false;
-
-      if ( simulationMode === SimulationMode.STAGED ) {
-
-        // Show 'Add a Mate' or 'Play' button, depending on the size of the population.
-        // Make one of these buttons visible on the next frame, so that a double-click on the 'Start Over' button
-        // doesn't fire the button that is made visible. See https://github.com/phetsims/natural-selection/issues/166
-        const bunnyCount = bunnyCountProperty.value;
-        stepTimer.runOnNextTick( () => {
-
-          // Checking simulationModeProperty to make sure it hasn't changed again before this callback fires.
-          // See https://github.com/phetsims/natural-selection/issues/235
-          if ( simulationModeProperty.value === SimulationMode.STAGED ) {
-            addAMateButton.visible = ( bunnyCount === 1 );
-            playButton.visible = ( bunnyCount > 1 );
-          }
+        // start with all buttons hidden
+        addAMateButton.visible = false;
+        playButton.visible = false;
+        startOverButton.visible = false;
+
+        if ( simulationMode === SimulationMode.STAGED ) {
+
+          // Show 'Add a Mate' or 'Play' button, depending on the size of the population.
+          // Make one of these buttons visible on the next frame, so that a double-click on the 'Start Over' button
+          // doesn't fire the button that is made visible. See https://github.com/phetsims/natural-selection/issues/166
+          const bunnyCount = bunnyCountProperty.value;
+          stepTimer.runOnNextTick( () => {
+
+            // Checking simulationModeProperty to make sure it hasn't changed again before this callback fires.
+            // See https://github.com/phetsims/natural-selection/issues/235
+            if ( simulationModeProperty.value === SimulationMode.STAGED ) {
+              addAMateButton.visible = ( bunnyCount === 1 );
+              playButton.visible = ( bunnyCount > 1 );
+            }
           } );
         }
         else if ( simulationMode === SimulationMode.ACTIVE ) {