diff --git a/Platform/Apple/tools/jace/src/main/java/jace/EmulatorUILogic.java b/Platform/Apple/tools/jace/src/main/java/jace/EmulatorUILogic.java
index 7872f39b..d108f9fb 100644
--- a/Platform/Apple/tools/jace/src/main/java/jace/EmulatorUILogic.java
+++ b/Platform/Apple/tools/jace/src/main/java/jace/EmulatorUILogic.java
@@ -275,6 +275,7 @@ public class EmulatorUILogic implements Reconfigurable {
             Stage stage = LawlessLegends.getApplication().primaryStage;
             stage.setFullScreenExitKeyCombination(KeyCombination.NO_MATCH);
             stage.setFullScreen(!stage.isFullScreen());
+            LawlessLegends.getApplication().controller.setAspectRatioEnabled(stage.isFullScreen());
         });
     }
 
@@ -406,37 +407,41 @@ public class EmulatorUILogic implements Reconfigurable {
                     || LawlessLegends.getApplication().primaryStage == null) {
                 return;
             }
+            Stage stage = LawlessLegends.getApplication().primaryStage;
             size++;
             if (size > 3) {
                 size = 0;
             }
-            int width = 0, height = 0;
-            switch (size) {
-                case 0: // 1x
-                    width = 560;
-                    height = 384;
-                    break;
-                case 1: // 1.5x
-                    width = 840;
-                    height = 576;
-                    break;
-                case 2: // 2x
-                    width = 560 * 2;
-                    height = 384 * 2;
-                    break;
-                case 3: // 3x (retina) 2880x1800
-                    width = 560 * 3;
-                    height = 384 * 3;
-                    break;
-                default: // 2x
-                    width = 560 * 2;
-                    height = 384 * 2;
+            if (stage.isFullScreen()) {
+                LawlessLegends.getApplication().controller.toggleAspectRatio();
+            } else {
+                int width = 0, height = 0;
+                switch (size) {
+                    case 0: // 1x
+                        width = 560;
+                        height = 384;
+                        break;
+                    case 1: // 1.5x
+                        width = 840;
+                        height = 576;
+                        break;
+                    case 2: // 2x
+                        width = 560 * 2;
+                        height = 384 * 2;
+                        break;
+                    case 3: // 3x (retina) 2880x1800
+                        width = 560 * 3;
+                        height = 384 * 3;
+                        break;
+                    default: // 2x
+                        width = 560 * 2;
+                        height = 384 * 2;
+                }
+                double vgap = stage.getScene().getY();
+                double hgap = stage.getScene().getX();
+                stage.setWidth(hgap * 2 + width);
+                stage.setHeight(vgap + height);
             }
-            Stage stage = LawlessLegends.getApplication().primaryStage;
-            double vgap = stage.getScene().getY();
-            double hgap = stage.getScene().getX();
-            stage.setWidth(hgap * 2 + width);
-            stage.setHeight(vgap + height);
         });
     }
 
diff --git a/Platform/Apple/tools/jace/src/main/java/jace/JaceUIController.java b/Platform/Apple/tools/jace/src/main/java/jace/JaceUIController.java
index 812e6979..177c4375 100644
--- a/Platform/Apple/tools/jace/src/main/java/jace/JaceUIController.java
+++ b/Platform/Apple/tools/jace/src/main/java/jace/JaceUIController.java
@@ -29,6 +29,11 @@ import java.util.concurrent.TimeUnit;
 import java.util.logging.Level;
 import java.util.logging.Logger;
 import javafx.application.Platform;
+import javafx.beans.binding.DoubleBinding;
+import javafx.beans.binding.NumberBinding;
+import javafx.beans.binding.When;
+import javafx.beans.property.BooleanProperty;
+import javafx.beans.property.SimpleBooleanProperty;
 import javafx.event.EventHandler;
 import javafx.fxml.FXML;
 import javafx.geometry.Insets;
@@ -71,13 +76,19 @@ public class JaceUIController {
 
     Computer computer;
 
+    private BooleanProperty aspectRatioCorrectionEnabled = new SimpleBooleanProperty(false);
+
     @FXML
     void initialize() {
         assert rootPane != null : "fx:id=\"rootPane\" was not injected: check your FXML file 'JaceUI.fxml'.";
         assert stackPane != null : "fx:id=\"stackPane\" was not injected: check your FXML file 'JaceUI.fxml'.";
         assert notificationBox != null : "fx:id=\"notificationBox\" was not injected: check your FXML file 'JaceUI.fxml'.";
         assert appleScreen != null : "fx:id=\"appleScreen\" was not injected: check your FXML file 'JaceUI.fxml'.";
-        appleScreen.fitWidthProperty().bind(rootPane.widthProperty());
+        NumberBinding aspectCorrectedWidth = rootPane.heightProperty().multiply(3.0).divide(2.0);
+        NumberBinding width = new When(
+                aspectRatioCorrectionEnabled.and(aspectCorrectedWidth.lessThan(rootPane.widthProperty()))
+        ).then(aspectCorrectedWidth).otherwise(rootPane.widthProperty());
+        appleScreen.fitWidthProperty().bind(width);
         appleScreen.fitHeightProperty().bind(rootPane.heightProperty());
         appleScreen.setVisible(false);
         rootPane.setOnDragEntered(this::processDragEnteredEvent);
@@ -85,6 +96,14 @@ public class JaceUIController {
         rootPane.setBackground(new Background(new BackgroundFill(Color.BLACK, null, null)));
     }
 
+    public void toggleAspectRatio() {
+        setAspectRatioEnabled(aspectRatioCorrectionEnabled.not().get());
+    }
+
+    public void setAspectRatioEnabled(boolean enabled) {
+        aspectRatioCorrectionEnabled.set(enabled);
+    }
+
     public void connectComputer(Computer computer, Stage primaryStage) {
         if (computer == null) {
             return;