diff --git a/js/components/WindowManager.js b/js/components/WindowManager.js
index b5a91cad..a31e5816 100644
--- a/js/components/WindowManager.js
+++ b/js/components/WindowManager.js
@@ -64,15 +64,12 @@ class WindowManager extends React.Component {
       const boxWidth = bounding.right - bounding.left;
 
       const move = {
-        x: Math.ceil(offsetLeft - bounding.left + (width - boxWidth) / 2),
-        y: Math.ceil(offsetTop - bounding.top + (height - boxHeight) / 2)
+        x: Math.ceil(offsetLeft + (width - boxWidth) / 2),
+        y: Math.ceil(offsetTop + (height - boxHeight) / 2)
       };
 
       const newPositions = this.props.windowsInfo.reduce(
-        (pos, w) => ({
-          ...pos,
-          [w.key]: { x: move.x + w.x, y: move.y + w.y }
-        }),
+        (pos, w) => ({ ...pos, [w.key]: { x: move.x + w.x, y: move.y + w.y } }),
         {}
       );
 
diff --git a/js/utils.ts b/js/utils.ts
index 5c2a4ef5..bebf80b5 100644
--- a/js/utils.ts
+++ b/js/utils.ts
@@ -328,19 +328,15 @@ interface Window {
 }
 
 export const calculateBoundingBox = (windows: Window[]) =>
-  windows
-    .map(w => ({
-      left: w.x,
-      top: w.y,
-      bottom: w.y + w.height,
-      right: w.x + w.width
-    }))
-    .reduce((b, w) => ({
-      left: Math.min(b.left, w.left),
-      top: Math.min(b.top, w.top),
-      bottom: Math.max(b.bottom, w.bottom),
-      right: Math.max(b.right, w.right)
-    }));
+  windows.reduce(
+    (b, w) => ({
+      left: Math.min(b.left, w.x),
+      top: Math.min(b.top, w.y),
+      bottom: Math.max(b.bottom, w.y + w.height),
+      right: Math.max(b.right, w.x + w.width)
+    }),
+    { top: 0, bottom: 0, left: 0, right: 0 }
+  );
 
 export function findLastIndex<T>(arr: T[], cb: (val: T) => boolean) {
   for (let i = arr.length - 1; i >= 0; i--) {