update

layout/includes/third-party/pjax.pug

@@ -65,12 +65,13 @@ script.
     })
 
     document.addEventListener('pjax:error', e => {
-      if (e.request.status === 404) {
+      const responseURL = e.request && e.request.responseURL
+      if (e.request && e.request.status === 404) {
         !{theme.error_404 && theme.error_404.enable}
           ? pjax.loadUrl('!{url_for("/404.html")}')
-          : window.location.href = e.request.responseURL
-      } else {
-        window.location.href = e.request.responseURL
+          : responseURL && (window.location.href = responseURL)
+      } else if (responseURL) {
+        window.location.href = responseURL
       }
     })
   })