From 6a317569d798a5d79e0cc2ef511864a15cb73c0c Mon Sep 17 00:00:00 2001
From: Luke Barnard <luke@matrix.org>
Date: Mon, 4 Jun 2018 09:38:21 +0100
Subject: [PATCH] Add null-guard to support browsers that don't support
 performance

Like Tor.

Fixes https://github.com/vector-im/riot-web/issues/6781
---
 src/components/structures/MatrixChat.js | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/src/components/structures/MatrixChat.js b/src/components/structures/MatrixChat.js
index 46c1113a1d..e1c9e33055 100644
--- a/src/components/structures/MatrixChat.js
+++ b/src/components/structures/MatrixChat.js
@@ -398,6 +398,9 @@ export default React.createClass({
     },
 
     startPageChangeTimer() {
+        // Tor doesn't support performance
+        if (!performance || !performance.mark) return null;
+
         // This shouldn't happen because componentWillUpdate and componentDidUpdate
         // are used.
         if (this._pageChanging) {
@@ -409,6 +412,9 @@ export default React.createClass({
     },
 
     stopPageChangeTimer() {
+        // Tor doesn't support performance
+        if (!performance || !performance.mark) return null;
+
         if (!this._pageChanging) {
             console.warn('MatrixChat.stopPageChangeTimer: timer not started');
             return;