From c93df2159fbd3888a5c48d8a8b8ae61dbbc54b89 Mon Sep 17 00:00:00 2001
From: Matt Panaro <matt.panaro@gmail.com>
Date: Fri, 27 Dec 2019 09:43:09 -0500
Subject: [PATCH] cache currently-viewing status id to avoid calling redux with
 identical value

---
 app/javascript/mastodon/components/status_list.js | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/app/javascript/mastodon/components/status_list.js b/app/javascript/mastodon/components/status_list.js
index ecfdddba83..82e069601d 100644
--- a/app/javascript/mastodon/components/status_list.js
+++ b/app/javascript/mastodon/components/status_list.js
@@ -60,6 +60,12 @@ export default class StatusList extends ImmutablePureComponent {
     this.props.onLoadMore(this.props.statusIds.size > 0 ? this.props.statusIds.last() : undefined);
   }, 300, { leading: true })
 
+  updateCurrentlyViewingWithCache = (id) => {
+    if(this.cachedCurrentlyViewing === id) return;
+    this.cachedCurrentlyViewing = id;
+    this.props.updateCurrentlyViewing(id);
+  }
+
   _selectChild (index, align_top) {
     const container = this.node.node;
     const element = container.querySelector(`article:nth-of-type(${index + 1}) .focusable`);
@@ -81,6 +87,7 @@ export default class StatusList extends ImmutablePureComponent {
   render () {
     const { statusIds, featuredStatusIds, shouldUpdateScroll, onLoadMore, timelineId, ...other }  = this.props;
     const { isLoading, isPartial } = other;
+    other.updateCurrentlyViewing = this.updateCurrentlyViewingWithCache;
 
     if (isPartial) {
       return <RegenerationIndicator />;