diff --git a/source/engine/viewer/viewergeometry.js b/source/engine/viewer/viewergeometry.js
index bac5171..2305fe2 100644
--- a/source/engine/viewer/viewergeometry.js
+++ b/source/engine/viewer/viewergeometry.js
@@ -194,6 +194,10 @@ export class ViewerGeometry
             return null;
         }
 
+        if (mouseCoords.x < 0.0 || mouseCoords.x > width || mouseCoords.y < 0.0 || mouseCoords.y > height) {
+            return null;
+        }
+
         let raycaster = new THREE.Raycaster ();
         let mousePos = new THREE.Vector2 ();
         mousePos.x = (mouseCoords.x / width) * 2 - 1;
diff --git a/source/website/modal.js b/source/website/modal.js
index 337caf3..436750c 100644
--- a/source/website/modal.js
+++ b/source/website/modal.js
@@ -6,6 +6,10 @@ export class Modal
     constructor ()
     {
         this.modalDiv = CreateDiv ('ov_modal');
+        this.modalDiv.addEventListener ('mousemove', (ev) => {
+            ev.stopPropagation ();
+        });
+
         this.overlayDiv = null;
         this.resizeHandler = null;
         this.positionCalculator = null;
@@ -46,6 +50,9 @@ export class Modal
                 ev.preventDefault ();
                 this.Close ();
             });
+            this.overlayDiv.addEventListener ('mousemove', (ev) => {
+                ev.stopPropagation ();
+            });
             this.overlayDiv.addEventListener ('contextmenu', (ev) => {
                 ev.preventDefault ();
                 this.Close ();
diff --git a/source/website/website.js b/source/website/website.js
index 35adb4a..445cbb4 100644
--- a/source/website/website.js
+++ b/source/website/website.js
@@ -203,7 +203,6 @@ export class Website
     {
         if (this.measureTool.IsActive ()) {
             this.measureTool.MouseMove (mouseCoordinates);
-            return;
         }
     }