diff --git a/app/assets/javascripts/post_tooltips.js.erb b/app/assets/javascripts/post_tooltips.js.erb
index 14229c46e..1b45bb047 100644
--- a/app/assets/javascripts/post_tooltips.js.erb
+++ b/app/assets/javascripts/post_tooltips.js.erb
@@ -28,7 +28,8 @@ Danbooru.PostTooltip.QTIP_OPTIONS = {
     my: "top left",
     at: "bottom left",
     target: "mouse",
-    // viewport: $(window), // XXX broken on jquery-ui 1.11; add back after upgrading to jquery-ui 1.12.
+    // `viewport: $(window)` is better, but it requires jquery-migrate until https://github.com/qTip2/qTip2/issues/797 is fixed.
+    viewport: true,
     adjust: {
       mouse: false,
       y: 25,