From 11436358b4091c58532603adcd0f8b9d2e9e7775 Mon Sep 17 00:00:00 2001
From: Eugen Rochko <eugen@zeonfederated.com>
Date: Sat, 7 Oct 2017 12:16:39 +0200
Subject: [PATCH] Fix regression from #5206 - deduplicate descendants (#5253)

---
 app/javascript/mastodon/reducers/contexts.js | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/app/javascript/mastodon/reducers/contexts.js b/app/javascript/mastodon/reducers/contexts.js
index d8924e908..64d584a01 100644
--- a/app/javascript/mastodon/reducers/contexts.js
+++ b/app/javascript/mastodon/reducers/contexts.js
@@ -34,7 +34,13 @@ const deleteFromContexts = (state, id) => {
 const updateContext = (state, status, references) => {
   return state.update('descendants', map => {
     references.forEach(parentId => {
-      map = map.update(parentId, ImmutableList(), list => list.push(status.id));
+      map = map.update(parentId, ImmutableList(), list => {
+        if (list.includes(status.id)) {
+          return list;
+        }
+
+        return list.push(status.id);
+      });
     });
 
     return map;