From 879832a4eb0bfaaa3c44f2e6293d6cd4a9260877 Mon Sep 17 00:00:00 2001
From: Michael Telatynski <7t3chguy@gmail.com>
Date: Thu, 29 Jun 2023 09:19:18 +0100
Subject: [PATCH] Fix spurious error sending receipt in thread errors (#11157)

Trying to send an RR to the first event fails in threads
as that event is a thread root and cannot carry a threaded RR
so instead target the last event
---
 src/components/structures/TimelinePanel.tsx | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/components/structures/TimelinePanel.tsx b/src/components/structures/TimelinePanel.tsx
index d9dfa64493..061aa9d10e 100644
--- a/src/components/structures/TimelinePanel.tsx
+++ b/src/components/structures/TimelinePanel.tsx
@@ -1135,7 +1135,7 @@ class TimelinePanel extends React.Component<IProps, IState> {
         const lastReadEventIndex = this.getLastDisplayedEventIndex({
             ignoreOwn: true,
         });
-        const lastReadEvent: MatrixEvent | null = this.state.events[lastReadEventIndex ?? 0] ?? null;
+        const lastReadEvent = this.state.events[lastReadEventIndex ?? this.state.events.length - 1] ?? null;
 
         const shouldSendReadReceipt = this.shouldSendReadReceipt(
             currentReadReceiptEventId,