diff --git a/indra/llmessage/llcoproceduremanager.cpp b/indra/llmessage/llcoproceduremanager.cpp
index 25c1c015f8..80caabda56 100644
--- a/indra/llmessage/llcoproceduremanager.cpp
+++ b/indra/llmessage/llcoproceduremanager.cpp
@@ -138,13 +138,24 @@ LLCoprocedureManager::~LLCoprocedureManager()
     close();
 }
 
-LLCoprocedureManager::poolPtr_t LLCoprocedureManager::initializePool(const std::string &poolName)
+void LLCoprocedureManager::initializePool(const std::string &poolName)
 {
+    poolMap_t::iterator it = mPoolMap.find(poolName);
+
+    if (it != mPoolMap.end())
+    {
+        // Pools are not supposed to be initialized twice
+        // Todo: ideally restrict init to STATE_FIRST
+        LL_ERRS() << "Pool is already present " << poolName << LL_ENDL;
+        return;
+    }
+
     // Attempt to look up a pool size in the configuration.  If found use that
     std::string keyName = "PoolSize" + poolName;
     int size = 0;
 
     LL_ERRS_IF(poolName.empty(), "CoprocedureManager") << "Poolname must not be empty" << LL_ENDL;
+    LL_INFOS("CoprocedureManager") << "Initializing pool " << poolName << LL_ENDL;
 
     if (mPropertyQueryFn)
     {
@@ -171,8 +182,6 @@ LLCoprocedureManager::poolPtr_t LLCoprocedureManager::initializePool(const std::
 
     bool inserted = mPoolMap.emplace(poolName, pool).second;
     LL_ERRS_IF(!inserted, "CoprocedureManager") << "Unable to add pool named \"" << poolName << "\" to map. FATAL!" << LL_ENDL;
-
-    return pool;
 }
 
 //-------------------------------------------------------------------------
@@ -182,21 +191,28 @@ LLUUID LLCoprocedureManager::enqueueCoprocedure(const std::string &pool, const s
     // not exist, create it.
     poolMap_t::iterator it = mPoolMap.find(pool);
 
-    poolPtr_t targetPool = (it != mPoolMap.end()) ? it->second : initializePool(pool);
+    if (it == mPoolMap.end())
+    {
+        // initializing pools in enqueueCoprocedure is not thread safe,
+        // at the moment pools need to be initialized manually
+        LL_ERRS() << "Uninitialized pool " << pool << LL_ENDL;
+    }
 
+    poolPtr_t targetPool = it->second;
     return targetPool->enqueueCoprocedure(name, proc);
 }
 
 void LLCoprocedureManager::setPropertyMethods(SettingQuery_t queryfn, SettingUpdate_t updatefn)
 {
     // functions to discover and store the pool sizes
+    // Might be a better idea to make an initializePool(name, size) to init everything externally
     mPropertyQueryFn = queryfn;
     mPropertyDefineFn = updatefn;
 
-    // workaround until we get mutex into initializePool
-    initializePool("VAssetStorage");
     initializePool("Upload");
-    initializePool("ExpCache"); // <FS:Ansariel> FIRE-30731: ExpCache coroutine pool crash
+    initializePool("AIS"); // it might be better to have some kind of on-demand initialization for AIS
+    // "ExpCache" pool gets initialized in LLExperienceCache
+    // asset storage pool gets initialized in LLViewerAssetStorage
 }
 
 //-------------------------------------------------------------------------
diff --git a/indra/llmessage/llcoproceduremanager.h b/indra/llmessage/llcoproceduremanager.h
index 70204ba02b..d6973996a9 100644
--- a/indra/llmessage/llcoproceduremanager.h
+++ b/indra/llmessage/llcoproceduremanager.h
@@ -79,6 +79,8 @@ public:
 
     void close();
     void close(const std::string &pool);
+
+    void initializePool(const std::string &poolName);
     
 private:
 
@@ -87,8 +89,6 @@ private:
 
     poolMap_t mPoolMap;
 
-    poolPtr_t initializePool(const std::string &poolName);
-
     SettingQuery_t mPropertyQueryFn;
     SettingUpdate_t mPropertyDefineFn;
 };
diff --git a/indra/llmessage/llexperiencecache.cpp b/indra/llmessage/llexperiencecache.cpp
index 05da0c57f2..225993c4af 100644
--- a/indra/llmessage/llexperiencecache.cpp
+++ b/indra/llmessage/llexperiencecache.cpp
@@ -114,6 +114,8 @@ void LLExperienceCache::initSingleton()
         cache_stream >> (*this);
     }
 
+    LLCoprocedureManager::instance().initializePool("ExpCache");
+
     LLCoros::instance().launch("LLExperienceCache::idleCoro",
         boost::bind(&LLExperienceCache::idleCoro, this));
 
diff --git a/indra/llmessage/tests/llcoproceduremanager_test.cpp b/indra/llmessage/tests/llcoproceduremanager_test.cpp
index 9db13a37b5..6424117ef3 100644
--- a/indra/llmessage/tests/llcoproceduremanager_test.cpp
+++ b/indra/llmessage/tests/llcoproceduremanager_test.cpp
@@ -91,6 +91,7 @@ namespace tut
     {
         Sync sync;
         int foo = 0;
+        LLCoprocedureManager::instance().initializePool("PoolName");
         LLUUID queueId = LLCoprocedureManager::instance().enqueueCoprocedure("PoolName", "ProcName",
             [&foo, &sync] (LLCoreHttpUtil::HttpCoroutineAdapter::ptr_t & ptr, const LLUUID & id) {
                 sync.bump();
diff --git a/indra/newview/llenvironment.cpp b/indra/newview/llenvironment.cpp
index fa6d489310..f9827a5e25 100644
--- a/indra/newview/llenvironment.cpp
+++ b/indra/newview/llenvironment.cpp
@@ -1899,8 +1899,11 @@ void LLEnvironment::recordEnvironment(S32 parcel_id, LLEnvironment::EnvironmentI
         }
         else
         {
-            setEnvironment(ENV_REGION, envinfo->mDayCycle, envinfo->mDayLength, envinfo->mDayOffset, envinfo->mEnvVersion);
             mTrackAltitudes = envinfo->mAltitudes;
+            // update track selection based on new altitudes
+            mCurrentTrack = calculateSkyTrackForAltitude(gAgent.getPositionAgent().mV[VZ]);
+
+            setEnvironment(ENV_REGION, envinfo->mDayCycle, envinfo->mDayLength, envinfo->mDayOffset, envinfo->mEnvVersion);
         }
 
         LL_DEBUGS("ENVIRONMENT") << "Altitudes set to {" << mTrackAltitudes[0] << ", "<< mTrackAltitudes[1] << ", " << mTrackAltitudes[2] << ", " << mTrackAltitudes[3] << LL_ENDL;
@@ -2524,6 +2527,15 @@ void LLEnvironment::onAgentPositionHasChanged(const LLVector3 &localpos)
         return;
 
     mCurrentTrack = trackno;
+
+    LLViewerRegion* cur_region = gAgent.getRegion();
+    if (!cur_region || !cur_region->capabilitiesReceived())
+    {
+        // Environment not ready, environment will be updated later, don't cause 'blend' yet.
+        // But keep mCurrentTrack updated in case we won't get new altitudes for some reason
+        return;
+    }
+
     for (S32 env = ENV_LOCAL; env < ENV_DEFAULT; ++env)
     {
         if (mEnvironments[env])
diff --git a/indra/newview/llstartup.cpp b/indra/newview/llstartup.cpp
index 7a839d7b1b..b495a87377 100644
--- a/indra/newview/llstartup.cpp
+++ b/indra/newview/llstartup.cpp
@@ -2579,9 +2579,6 @@ bool idle_startup()
 		
 		display_startup();
 
-		//all categories loaded. lets create "My Favorites" category
-		gInventory.findCategoryUUIDForType(LLFolderType::FT_FAVORITE,true);
-
 		// set up callbacks
 		LL_INFOS() << "Registering Callbacks" << LL_ENDL;
 		LLMessageSystem* msg = gMessageSystem;
diff --git a/indra/newview/llviewerassetstorage.cpp b/indra/newview/llviewerassetstorage.cpp
index 9d1e5c9c1f..6d28aebc28 100644
--- a/indra/newview/llviewerassetstorage.cpp
+++ b/indra/newview/llviewerassetstorage.cpp
@@ -117,6 +117,7 @@ LLViewerAssetStorage::LLViewerAssetStorage(LLMessageSystem *msg, LLXferManager *
       mCountSucceeded(0),
       mTotalBytesFetched(0)
 {
+    LLCoprocedureManager::instance().initializePool(VIEWER_ASSET_STORAGE_CORO_POOL);
 }
 
 
@@ -130,6 +131,7 @@ LLViewerAssetStorage::LLViewerAssetStorage(LLMessageSystem *msg, LLXferManager *
       mCountSucceeded(0),
       mTotalBytesFetched(0)
 {
+    LLCoprocedureManager::instance().initializePool(VIEWER_ASSET_STORAGE_CORO_POOL);
 }
 
 LLViewerAssetStorage::~LLViewerAssetStorage()