diff --git a/src/core/platform/web/dom.js b/src/core/platform/web/dom.js
index 945aa359a..6a2f3fb95 100644
--- a/src/core/platform/web/dom.js
+++ b/src/core/platform/web/dom.js
@@ -448,7 +448,7 @@
                 viewportBounds = document.documentElement.getBoundingClientRect();
             var left;
             if (comboRect.left + comboRect.width / 2 + popupRect.width / 2 > viewportBounds.width) {
-                left = viewportBounds.width - comboRect.width - positionRelativeElementRect.left;
+                left = viewportBounds.width - popupRect.width - positionRelativeElementRect.left;
             } else {
                 left = comboRect.left + (comboRect.width - popupRect.width) / 2 - positionRelativeElementRect.left;
             }