diff --git a/src/js/core/click_detector.js b/src/js/core/click_detector.js
index 557c1f28..1e332aa2 100644
--- a/src/js/core/click_detector.js
+++ b/src/js/core/click_detector.js
@@ -311,7 +311,7 @@ export class ClickDetector {
         const position = /** @type {typeof ClickDetector} */ (this.constructor).extractPointerPosition(event);
 
         if (event instanceof MouseEvent) {
-            const isRightClick = event.which == 3;
+            const isRightClick = event.button === 2;
             if (isRightClick) {
                 // Ignore right clicks
                 this.rightClick.dispatch(position, event);
@@ -384,7 +384,7 @@ export class ClickDetector {
         }
 
         if (event instanceof MouseEvent) {
-            const isRightClick = event.which == 3;
+            const isRightClick = event.button === 2;
             if (isRightClick) {
                 return;
             }
diff --git a/src/js/game/camera.js b/src/js/game/camera.js
index 930d6932..2e558216 100644
--- a/src/js/game/camera.js
+++ b/src/js/game/camera.js
@@ -436,11 +436,11 @@ export class Camera extends BasicSerializableObject {
         }
 
         this.touchPostMoveVelocity = new Vector(0, 0);
-        if (event.which === 1) {
+        if (event.button === 0) {
             this.combinedSingleTouchStartHandler(event.clientX, event.clientY);
-        } else if (event.which === 2) {
+        } else if (event.button === 1) {
             this.downPreHandler.dispatch(new Vector(event.clientX, event.clientY), enumMouseButton.middle);
-        } else if (event.which === 3) {
+        } else if (event.button === 2) {
             this.downPreHandler.dispatch(new Vector(event.clientX, event.clientY), enumMouseButton.right);
         }
         return false;
@@ -460,7 +460,7 @@ export class Camera extends BasicSerializableObject {
             return;
         }
 
-        if (event.which === 1) {
+        if (event.button === 0) {
             this.combinedSingleTouchMoveHandler(event.clientX, event.clientY);
         }