From fab3bbf70549957d82b1a696f8ac67d809d3de52 Mon Sep 17 00:00:00 2001
From: David Taylor <david@taylorhq.com>
Date: Wed, 18 Dec 2019 16:57:20 +0000
Subject: [PATCH] FIX: IE11 compatibility for readonly check

In some situations, the xhr object is undefined in IE11
---
 app/assets/javascripts/discourse/lib/ajax.js.es6 | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/app/assets/javascripts/discourse/lib/ajax.js.es6 b/app/assets/javascripts/discourse/lib/ajax.js.es6
index 4bb267812d5..54de18d4c8f 100644
--- a/app/assets/javascripts/discourse/lib/ajax.js.es6
+++ b/app/assets/javascripts/discourse/lib/ajax.js.es6
@@ -103,7 +103,7 @@ export function ajax() {
       run(() => {
         Site.currentProp(
           "isReadOnly",
-          !!xhr.getResponseHeader("Discourse-Readonly")
+          !!(xhr && xhr.getResponseHeader("Discourse-Readonly"))
         );
       });