diff --git a/app/initial_state.js b/app/initial_state.js
index 52097725d..5680735d6 100644
--- a/app/initial_state.js
+++ b/app/initial_state.js
@@ -40,6 +40,7 @@ const state = {
         posts: {
             posts: {},
             postsInChannel: {},
+            postsInThread: {},
             selectedPostId: '',
             currentFocusedPostId: '',
         },
diff --git a/app/store/middleware.js b/app/store/middleware.js
index 3281d8866..ccd7e7fa8 100644
--- a/app/store/middleware.js
+++ b/app/store/middleware.js
@@ -105,11 +105,6 @@ function resetStateForNewVersion(action) {
         i18n = payload.views.i18n;
     }
 
-    let fetchCache = initialState.views.fetchCache;
-    if (payload.views.fetchCache) {
-        fetchCache = payload.views.fetchCache;
-    }
-
     let lastTeamId = initialState.views.team.lastTeamId;
     if (payload.views.team && payload.views.team.lastTeamId) {
         lastTeamId = payload.views.team.lastTeamId;
@@ -147,7 +142,6 @@ function resetStateForNewVersion(action) {
                 drafts: channelDrafts,
             },
             i18n,
-            fetchCache,
             team: {
                 lastTeamId,
                 lastChannelForTeam,
@@ -190,6 +184,7 @@ function cleanupState(action, keepCurrent = false) {
         posts: {
             posts: {},
             postsInChannel: {},
+            postsInThread: {},
             reactions: {},
             openGraph: payload.entities.posts.openGraph,
             selectedPostId: payload.entities.posts.selectedPostId,
@@ -262,6 +257,11 @@ function cleanupState(action, keepCurrent = false) {
                     nextEntitites.files.files[fileId] = payload.entities.files.files[fileId];
                 });
             }
+
+            const postsInThread = payload.entities.posts.postsInThread[postId];
+            if (postsInThread) {
+                nextEntitites.posts.postsInThread[postId] = postsInThread;
+            }
         } else {
             // If the post is not in the store we need to remove it from the postsInChannel
             const channelIds = Object.keys(nextEntitites.posts.postsInChannel);
diff --git a/yarn.lock b/yarn.lock
index 4c20ee6a1..5acd4b982 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -4637,7 +4637,7 @@ map-visit@^1.0.0:
 
 mattermost-redux@mattermost/mattermost-redux:
   version "1.2.0"
-  resolved "https://codeload.github.com/mattermost/mattermost-redux/tar.gz/6725f81174fe4c8514f5217a3f05b6b0368f2642"
+  resolved "https://codeload.github.com/mattermost/mattermost-redux/tar.gz/10d691f386e1dbb7669ae549bbe81b855ef4c505"
   dependencies:
     deep-equal "1.0.1"
     form-data "2.3.1"