diff --git a/app/assets/javascripts/discourse/components/topic-navigation.js.es6 b/app/assets/javascripts/discourse/components/topic-navigation.js.es6
index bff5f73a2ee..7c96ccf00cf 100644
--- a/app/assets/javascripts/discourse/components/topic-navigation.js.es6
+++ b/app/assets/javascripts/discourse/components/topic-navigation.js.es6
@@ -43,11 +43,11 @@ export default Component.extend(PanEvents, {
           headerContainer = document.querySelector(".d-header"),
           headerHeight = (headerContainer && headerContainer.offsetHeight) || 0;
 
-        if (timelineContainer && composer) {
+        if (composer) {
           renderTimeline =
             width > MIN_WIDTH_TIMELINE &&
             window.innerHeight - composer.offsetHeight - headerHeight >
-              timelineContainer.offsetHeight;
+              (timelineContainer ? timelineContainer.offsetHeight : 0);
         }
       }