diff --git a/indra/llappearance/lltexlayer.cpp b/indra/llappearance/lltexlayer.cpp
index 278042c904..c00aa737e6 100644
--- a/indra/llappearance/lltexlayer.cpp
+++ b/indra/llappearance/lltexlayer.cpp
@@ -1431,6 +1431,12 @@ void LLTexLayer::renderMorphMasks(S32 x, S32 y, S32 width, S32 height, const LLC
             size_t mem_size        = pixels * bytes_per_pixel;
 
             alpha_data = (U8*)ll_aligned_malloc_32(mem_size);
+            if (!alpha_data)
+            {
+                LLError::LLUserWarningMsg::showOutOfMemory();
+                LL_ERRS() << "Failed to allocate memory for morph texture: " << (S32)(mem_size) << LL_ENDL;
+                return;
+            }
 
             bool skip_readback = LLRender::sNsightDebugSupport; // nSight doesn't support use of glReadPixels
 
@@ -1440,8 +1446,8 @@ void LLTexLayer::renderMorphMasks(S32 x, S32 y, S32 width, S32 height, const LLC
                 { // work-around for broken intel drivers which cannot do glReadPixels on an RGBA FBO
                     // returning only the alpha portion without locking up downstream
 
-                    // <FS:ND> glGetTexImagec will copy the whole texture, which might be   greater than width*height
-                    // Also what about the shenanigans with  passing bound_target around everywhere rather than use LLRenderTarget::getCurrentBoundTarget
+                    // <FS:ND> glGetTexImagec will copy the whole texture, which might be greater than width*height
+                    // Also what about the shenanigans with passing bound_target around everywhere rather than use LLRenderTarget::getCurrentBoundTarget
                     // Sometimes it also does happen that bound_target == nullptr but a render target ist bound
                     //
                     // U8* temp = (U8*)ll_aligned_malloc_32(mem_size << 2); // allocate same size, but RGBA
@@ -1492,8 +1498,14 @@ void LLTexLayer::renderMorphMasks(S32 x, S32 y, S32 width, S32 height, const LLC
                     llassert_always(y == 0);
 
                     // Not really needed to use aligned_malloc_32 here, but I suppose because we can and why not
-                    U8 *temp{ (U8*)ll_aligned_malloc_32(textureW * textureH * 4) };
+                    U8* temp{ (U8*)ll_aligned_malloc_32(textureW * textureH * 4) };
                     // </FS:ND>
+                    if (!temp)
+                    {
+                        LLError::LLUserWarningMsg::showOutOfMemory();
+                        LL_ERRS() << "Failed to allocate temporary memory for morph texture readback: " << (S32)(mem_size << 2) << LL_ENDL;
+                        return;
+                    }
 
                     glGetTexImage(LLTexUnit::getInternalType(LLTexUnit::TT_TEXTURE), 0, GL_RGBA, GL_UNSIGNED_BYTE, temp);
                     GLenum error = glGetError();
@@ -1531,6 +1543,12 @@ void LLTexLayer::renderMorphMasks(S32 x, S32 y, S32 width, S32 height, const LLC
                     // We just want GL_ALPHA, but that isn't supported in OGL core profile 4.
                     static const size_t TEMP_BYTES_PER_PIXEL = 4;
                     U8* temp_data = (U8*)ll_aligned_malloc_32(mem_size * TEMP_BYTES_PER_PIXEL);
+                    if (!temp_data)
+                    {
+                        LLError::LLUserWarningMsg::showOutOfMemory();
+                        LL_ERRS() << "Failed to allocate temporary memory for morph texture: " << (S32)(mem_size * TEMP_BYTES_PER_PIXEL) << LL_ENDL;
+                        return;
+                    }
                     glReadPixels(x, y, width, height, GL_RGBA, GL_UNSIGNED_BYTE, temp_data);
                     for (size_t pixel = 0; pixel < pixels; pixel++) {
                         alpha_data[pixel] = temp_data[(pixel * TEMP_BYTES_PER_PIXEL) + 3];
diff --git a/indra/newview/llface.cpp b/indra/newview/llface.cpp
index 01953b8a8b..29efffc745 100644
--- a/indra/newview/llface.cpp
+++ b/indra/newview/llface.cpp
@@ -2498,7 +2498,11 @@ F32 LLFace::adjustPartialOverlapPixelArea(F32 cos_angle_to_view_dir, F32 radius
 
         //the above calculation is too expensive
         //the below is a good estimation: bounding box of the bounding sphere:
-        F32 alpha = 0.5f * (radius + screen_radius - d) / radius ;
+        F32 alpha = 1.f;
+        if (!is_approx_zero(radius)) // radius can be something like -1e-10
+        {
+            alpha = 0.5f * (radius + screen_radius - d) / radius;
+        }
         alpha = llclamp(alpha, 0.f, 1.f) ;
         return alpha * alpha ;
     }
diff --git a/indra/newview/llfloatereditenvironmentbase.cpp b/indra/newview/llfloatereditenvironmentbase.cpp
index a42c94f049..bc1f3045bb 100644
--- a/indra/newview/llfloatereditenvironmentbase.cpp
+++ b/indra/newview/llfloatereditenvironmentbase.cpp
@@ -262,7 +262,7 @@ void LLFloaterEditEnvironmentBase::onSaveAsCommit(const LLSD& notification, cons
         }
         else if (mInventoryItem)
         {
-            const LLUUID &marketplacelistings_id = gInventory.findCategoryUUIDForType(LLFolderType::FT_MARKETPLACE_LISTINGS);
+            const LLUUID& marketplacelistings_id = gInventory.getMarketplaceListingsUUID();
             LLUUID parent_id = mInventoryItem->getParentUUID();
             if (marketplacelistings_id == parent_id || gInventory.isObjectDescendentOf(mInventoryItem->getUUID(), gInventory.getLibraryRootFolderID()))
             {
diff --git a/indra/newview/llfloatermarketplacelistings.cpp b/indra/newview/llfloatermarketplacelistings.cpp
index d51bf18327..89a7696a1a 100644
--- a/indra/newview/llfloatermarketplacelistings.cpp
+++ b/indra/newview/llfloatermarketplacelistings.cpp
@@ -29,6 +29,7 @@
 
 #include "llfloatermarketplacelistings.h"
 
+#include "llcallbacklist.h"
 #include "llfloaterreg.h"
 #include "llfiltereditor.h"
 #include "llfolderview.h"
@@ -232,7 +233,7 @@ void LLPanelMarketplaceListings::onTabChange()
 
 void LLPanelMarketplaceListings::onAddButtonClicked()
 {
-    LLUUID marketplacelistings_id = gInventory.findCategoryUUIDForType(LLFolderType::FT_MARKETPLACE_LISTINGS);
+    LLUUID marketplacelistings_id = gInventory.getMarketplaceListingsUUID();
     llassert(marketplacelistings_id.notNull());
     LLFolderType::EType preferred_type = LLFolderType::lookup("category");
     LLHandle<LLPanel> handle = getHandle();
@@ -352,7 +353,15 @@ public:
 
             if (added_category_type == LLFolderType::FT_MARKETPLACE_LISTINGS)
             {
-                mMarketplaceListingsFloater->initializeMarketPlace();
+                LLHandle<LLFloater> handle = mMarketplaceListingsFloater->getHandle();
+                doOnIdleOneTime([handle]()
+                {
+                    LLFloaterMarketplaceListings* floater = (LLFloaterMarketplaceListings*)handle.get();
+                    if (floater)
+                    {
+                        floater->initializeMarketPlace();
+                    }
+                });
             }
         }
     }
@@ -416,7 +425,7 @@ bool LLFloaterMarketplaceListings::postBuild()
     // Fetch aggressively so we can interact with listings as soon as possible
     if (!fetchContents())
     {
-        const LLUUID& marketplacelistings_id = gInventory.findCategoryUUIDForType(LLFolderType::FT_MARKETPLACE_LISTINGS);
+        const LLUUID& marketplacelistings_id = gInventory.getMarketplaceListingsUUID();
         LLInventoryModelBackgroundFetch::instance().start(marketplacelistings_id, true);
     }
 
@@ -514,8 +523,6 @@ void LLFloaterMarketplaceListings::setRootFolder()
         return;
     }
 
-    mRootFolderCreating = false;
-
     // No longer need to observe new category creation
     if (mCategoryAddedObserver && gInventory.containsObserver(mCategoryAddedObserver))
     {
@@ -525,6 +532,8 @@ void LLFloaterMarketplaceListings::setRootFolder()
     }
     llassert(!mCategoryAddedObserver);
 
+    mRootFolderCreating = false;
+
     if (marketplacelistings_id == mRootFolderId)
     {
         LL_WARNS("SLM") << "Inventory warning: Marketplace listings folder already set" << LL_ENDL;
@@ -567,7 +576,8 @@ void LLFloaterMarketplaceListings::setPanels()
 
 void LLFloaterMarketplaceListings::initializeMarketPlace()
 {
-    LLMarketplaceData::instance().initializeSLM(boost::bind(&LLFloaterMarketplaceListings::updateView, this));
+    if (!mRootFolderCreating)
+        LLMarketplaceData::instance().initializeSLM(boost::bind(&LLFloaterMarketplaceListings::updateView, this));
 }
 
 S32 LLFloaterMarketplaceListings::getFolderCount()
@@ -923,7 +933,7 @@ void LLFloaterMarketplaceValidation::onOpen(const LLSD& key)
     LLUUID cat_id(key.asUUID());
     if (cat_id.isNull())
     {
-        cat_id = gInventory.findCategoryUUIDForType(LLFolderType::FT_MARKETPLACE_LISTINGS);
+        cat_id = gInventory.getMarketplaceListingsUUID();
     }
 
     // Validates the folder
diff --git a/indra/newview/llfloaterpreference.cpp b/indra/newview/llfloaterpreference.cpp
index ae7c5b10a6..8ea3e0fa51 100644
--- a/indra/newview/llfloaterpreference.cpp
+++ b/indra/newview/llfloaterpreference.cpp
@@ -699,7 +699,8 @@ bool LLFloaterPreference::postBuild()
     getChild<LLUICtrl>("FSSoundCacheLocation")->setEnabled(false);
     // </FS:Ansariel>
 
-    getChild<LLComboBox>("language_combobox")->setCommitCallback(boost::bind(&LLFloaterPreference::onLanguageChange, this));
+    mLanguageCombobox = getChild<LLComboBox>("language_combobox");
+    mLanguageCombobox->setCommitCallback(boost::bind(&LLFloaterPreference::onLanguageChange, this));
     mTimeFormatCombobox = getChild<LLComboBox>("time_format_combobox");
     mTimeFormatCombobox->setCommitCallback(boost::bind(&LLFloaterPreference::onTimeFormatChange, this));
 
@@ -752,18 +753,18 @@ bool LLFloaterPreference::postBuild()
         std::map<std::string, std::string>::iterator iter = labels.find(system_lang);
         if (iter != labels.end())
         {
-            getChild<LLComboBox>("language_combobox")->add(iter->second, LLSD("default"), ADD_TOP, true);
+            mLanguageCombobox->add(iter->second, LLSD("default"), ADD_TOP, true);
         }
         else
         {
             LL_WARNS() << "Language \"" << system_lang << "\" is not in default_languages.xml" << LL_ENDL;
-            getChild<LLComboBox>("language_combobox")->add("System default", LLSD("default"), ADD_TOP, true);
+            mLanguageCombobox->add("System default", LLSD("default"), ADD_TOP, true);
         }
     }
     else
     {
         LL_WARNS() << "Failed to load labels from " << user_filename << ". Using default." << LL_ENDL;
-        getChild<LLComboBox>("language_combobox")->add("System default", LLSD("default"), ADD_TOP, true);
+        mLanguageCombobox->add("System default", LLSD("default"), ADD_TOP, true);
     }
 
 // <FS:Ansariel> Prefer FS-specific Discord implementation
@@ -2394,6 +2395,12 @@ void LLFloaterPreference::refresh()
     updateClickActionViews();
 
     mTimeFormatCombobox->selectByValue(gSavedSettings.getBOOL("Use24HourClock") ? "1" : "0");
+
+    std::string current_language = gSavedSettings.getString("Language");
+    if (current_language != "default" && !current_language.empty())
+    {
+        mLanguageCombobox->selectByValue(LLSD(current_language));
+    }
 }
 
 void LLFloaterPreference::onCommitWindowedMode()
diff --git a/indra/newview/llfloaterpreference.h b/indra/newview/llfloaterpreference.h
index 329d115a1f..1e93e24946 100644
--- a/indra/newview/llfloaterpreference.h
+++ b/indra/newview/llfloaterpreference.h
@@ -333,6 +333,7 @@ private:
     LLButton*       mEnablePopupBtn = nullptr;
     LLButton*       mDisablePopupBtn = nullptr;
     LLComboBox*     mTimeFormatCombobox = nullptr;
+    LLComboBox*     mLanguageCombobox = nullptr;
     std::unique_ptr< ll::prefs::SearchData > mSearchData;
     bool mSearchDataDirty;
 
diff --git a/indra/newview/llinventorybridge.cpp b/indra/newview/llinventorybridge.cpp
index 2a840110c4..bc0f02e6ab 100644
--- a/indra/newview/llinventorybridge.cpp
+++ b/indra/newview/llinventorybridge.cpp
@@ -377,7 +377,7 @@ bool LLInvFVBridge::cutToClipboard()
     const LLInventoryObject* obj = gInventory.getObject(mUUID);
     if (obj && isItemMovable() && isItemRemovable())
     {
-        const LLUUID &marketplacelistings_id = gInventory.findCategoryUUIDForType(LLFolderType::FT_MARKETPLACE_LISTINGS);
+        const LLUUID &marketplacelistings_id = gInventory.getMarketplaceListingsUUID();
         const bool cut_from_marketplacelistings = gInventory.isObjectDescendentOf(mUUID, marketplacelistings_id);
 
         if (cut_from_marketplacelistings && (LLMarketplaceData::instance().isInActiveFolder(mUUID) ||
@@ -1533,7 +1533,7 @@ bool LLInvFVBridge::isInboxFolder() const
 
 bool LLInvFVBridge::isMarketplaceListingsFolder() const
 {
-    const LLUUID folder_id = gInventory.findCategoryUUIDForType(LLFolderType::FT_MARKETPLACE_LISTINGS);
+    const LLUUID folder_id = gInventory.getMarketplaceListingsUUID();
 
     if (folder_id.isNull())
     {
@@ -1841,7 +1841,7 @@ bool LLInvFVBridge::canListOnMarketplaceNow() const
         {
             std::string error_msg;
             LLInventoryModel* model = getInventoryModel();
-            const LLUUID &marketplacelistings_id = model->findCategoryUUIDForType(LLFolderType::FT_MARKETPLACE_LISTINGS);
+            const LLUUID &marketplacelistings_id = model->getMarketplaceListingsUUID();
             if (marketplacelistings_id.notNull())
             {
                 LLViewerInventoryCategory * master_folder = model->getCategory(marketplacelistings_id);
@@ -2000,7 +2000,7 @@ void LLItemBridge::performAction(LLInventoryModel* model, std::string action)
     {
         LLInventoryItem* itemp = model->getItem(mUUID);
         if (!itemp) return;
-        const LLUUID &marketplacelistings_id = model->findCategoryUUIDForType(LLFolderType::FT_MARKETPLACE_LISTINGS);
+        const LLUUID& marketplacelistings_id = model->getMarketplaceListingsUUID();
         // Note: For a single item, if it's not a copy, then it's a move
         move_item_to_marketplacelistings(itemp, marketplacelistings_id, ("copy_to_marketplace_listings" == action));
     }
@@ -2960,7 +2960,7 @@ bool LLFolderBridge::dragCategoryIntoFolder(LLInventoryCategory* inv_cat,
 
     const LLUUID &cat_id = inv_cat->getUUID();
     const LLUUID &current_outfit_id = model->findCategoryUUIDForType(LLFolderType::FT_CURRENT_OUTFIT);
-    const LLUUID &marketplacelistings_id = model->findCategoryUUIDForType(LLFolderType::FT_MARKETPLACE_LISTINGS);
+    const LLUUID& marketplacelistings_id = model->getMarketplaceListingsUUID();
     const LLUUID from_folder_uuid = inv_cat->getParentUUID();
 
     const bool move_is_into_current_outfit = (mUUID == current_outfit_id);
@@ -4083,7 +4083,7 @@ void LLFolderBridge::performAction(LLInventoryModel* model, std::string action)
     {
         LLInventoryCategory * cat = gInventory.getCategory(mUUID);
         if (!cat) return;
-        const LLUUID &marketplacelistings_id = model->findCategoryUUIDForType(LLFolderType::FT_MARKETPLACE_LISTINGS);
+        const LLUUID& marketplacelistings_id = model->getMarketplaceListingsUUID();
         move_folder_to_marketplacelistings(cat, marketplacelistings_id, ("move_to_marketplace_listings" != action), (("copy_or_move_to_marketplace_listings" == action)));
     }
     else if ("copy_folder_uuid" == action)
@@ -4391,7 +4391,7 @@ void LLFolderBridge::pasteFromClipboard()
     LLInventoryModel* model = getInventoryModel();
     if (model && isClipboardPasteable())
     {
-        const LLUUID &marketplacelistings_id = model->findCategoryUUIDForType(LLFolderType::FT_MARKETPLACE_LISTINGS);
+        const LLUUID &marketplacelistings_id = model->getMarketplaceListingsUUID();
         const bool paste_into_marketplacelistings = model->isObjectDescendentOf(mUUID, marketplacelistings_id);
 
         bool cut_from_marketplacelistings = false;
@@ -4453,7 +4453,7 @@ void LLFolderBridge::perform_pasteFromClipboard()
     if (model && isClipboardPasteable())
     {
         const LLUUID &current_outfit_id = model->findCategoryUUIDForType(LLFolderType::FT_CURRENT_OUTFIT);
-        const LLUUID &marketplacelistings_id = model->findCategoryUUIDForType(LLFolderType::FT_MARKETPLACE_LISTINGS);
+        const LLUUID& marketplacelistings_id = model->getMarketplaceListingsUUID();
         const LLUUID &favorites_id = model->findCategoryUUIDForType(LLFolderType::FT_FAVORITE);
         const LLUUID &my_outifts_id = model->findCategoryUUIDForType(LLFolderType::FT_MY_OUTFITS);
         const LLUUID &lost_and_found_id = model->findCategoryUUIDForType(LLFolderType::FT_LOST_AND_FOUND);
@@ -4776,7 +4776,7 @@ void LLFolderBridge::pasteLinkFromClipboard()
     if(model)
     {
         const LLUUID &current_outfit_id = model->findCategoryUUIDForType(LLFolderType::FT_CURRENT_OUTFIT);
-        const LLUUID &marketplacelistings_id = model->findCategoryUUIDForType(LLFolderType::FT_MARKETPLACE_LISTINGS);
+        const LLUUID& marketplacelistings_id = model->getMarketplaceListingsUUID();
         const LLUUID &my_outifts_id = model->findCategoryUUIDForType(LLFolderType::FT_MY_OUTFITS);
 
         const bool move_is_into_current_outfit = (mUUID == current_outfit_id);
@@ -4876,7 +4876,7 @@ void LLFolderBridge::buildContextMenuOptions(U32 flags, menuentry_vec_t&   items
     const LLUUID &trash_id = model->findCategoryUUIDForType(LLFolderType::FT_TRASH);
     const LLUUID &lost_and_found_id = model->findCategoryUUIDForType(LLFolderType::FT_LOST_AND_FOUND);
     const LLUUID &favorites = model->findCategoryUUIDForType(LLFolderType::FT_FAVORITE);
-    const LLUUID &marketplace_listings_id = model->findCategoryUUIDForType(LLFolderType::FT_MARKETPLACE_LISTINGS);
+    const LLUUID& marketplace_listings_id = model->getMarketplaceListingsUUID();
     const LLUUID &outfits_id = model->findCategoryUUIDForType(LLFolderType::FT_MY_OUTFITS);
 
     // <FS:Ansariel> FIRE-11628: Option to delete broken links from AO folder
@@ -6281,7 +6281,7 @@ bool LLFolderBridge::dragItemIntoFolder(LLInventoryItem* inv_item,
     const LLUUID &favorites_id = model->findCategoryUUIDForType(LLFolderType::FT_FAVORITE);
     // <FS:Ansariel> FIRE-1392: Allow dragging all asset types into Landmarks folder
     //const LLUUID &landmarks_id = model->findCategoryUUIDForType(LLFolderType::FT_LANDMARK);
-    const LLUUID &marketplacelistings_id = model->findCategoryUUIDForType(LLFolderType::FT_MARKETPLACE_LISTINGS);
+    const LLUUID& marketplacelistings_id = model->getMarketplaceListingsUUID();
     const LLUUID &my_outifts_id = model->findCategoryUUIDForType(LLFolderType::FT_MY_OUTFITS);
     const LLUUID from_folder_uuid = inv_item->getParentUUID();
 
diff --git a/indra/newview/llinventoryfunctions.cpp b/indra/newview/llinventoryfunctions.cpp
index c468e3b948..e68f61bd68 100644
--- a/indra/newview/llinventoryfunctions.cpp
+++ b/indra/newview/llinventoryfunctions.cpp
@@ -417,7 +417,7 @@ void update_all_marketplace_count(const LLUUID& cat_id)
 void update_all_marketplace_count()
 {
     // Get the marketplace root and launch the recursive exploration
-    const LLUUID marketplace_listings_uuid = gInventory.findCategoryUUIDForType(LLFolderType::FT_MARKETPLACE_LISTINGS);
+    const LLUUID marketplace_listings_uuid = gInventory.getMarketplaceListingsUUID();
     if (!marketplace_listings_uuid.isNull())
     {
         update_all_marketplace_count(marketplace_listings_uuid);
@@ -1204,11 +1204,7 @@ void open_marketplace_listings()
 
 S32 depth_nesting_in_marketplace(LLUUID cur_uuid)
 {
-    // Get the marketplace listings root, exit with -1 (i.e. not under the marketplace listings root) if none
-    // Todo: findCategoryUUIDForType is somewhat expensive with large
-    // flat root folders yet we use depth_nesting_in_marketplace at
-    // every turn, find a way to correctly cache this id.
-    const LLUUID marketplace_listings_uuid = gInventory.findCategoryUUIDForType(LLFolderType::FT_MARKETPLACE_LISTINGS);
+    const LLUUID marketplace_listings_uuid = gInventory.getMarketplaceListingsUUID();
     if (marketplace_listings_uuid.isNull())
     {
         return -1;
@@ -3626,7 +3622,7 @@ void LLInventoryAction::doToSelected(LLInventoryModel* model, LLFolderView* root
 
     if ("delete" == action)
     {
-        const LLUUID &marketplacelistings_id = gInventory.findCategoryUUIDForType(LLFolderType::FT_MARKETPLACE_LISTINGS);
+        const LLUUID &marketplacelistings_id = gInventory.getMarketplaceListingsUUID();
         bool marketplacelistings_item = false;
         bool has_worn = false;
         bool needs_replacement = false;
@@ -3940,7 +3936,7 @@ void LLInventoryAction::doToSelected(LLInventoryModel* model, LLFolderView* root
     if (action == "wear" || action == "wear_add")
     {
         const LLUUID trash_id = gInventory.findCategoryUUIDForType(LLFolderType::FT_TRASH);
-        const LLUUID mp_id = gInventory.findCategoryUUIDForType(LLFolderType::FT_MARKETPLACE_LISTINGS);
+        const LLUUID mp_id = gInventory.getMarketplaceListingsUUID();
         std::copy_if(selected_uuid_set.begin(),
             selected_uuid_set.end(),
             std::back_inserter(ids),
@@ -4362,7 +4358,7 @@ void LLInventoryAction::buildMarketplaceFolders(LLFolderView* root)
     // target listing *and* the original listing. So we need to keep track of both.
     // Note: do not however put the marketplace listings root itself in this list or the whole marketplace data will be rebuilt.
     sMarketplaceFolders.clear();
-    const LLUUID &marketplacelistings_id = gInventory.findCategoryUUIDForType(LLFolderType::FT_MARKETPLACE_LISTINGS);
+    const LLUUID& marketplacelistings_id = gInventory.getMarketplaceListingsUUID();
     if (marketplacelistings_id.isNull())
     {
         return;
diff --git a/indra/newview/llinventorygallery.cpp b/indra/newview/llinventorygallery.cpp
index 272a4ca51c..d4d26509d1 100644
--- a/indra/newview/llinventorygallery.cpp
+++ b/indra/newview/llinventorygallery.cpp
@@ -1726,7 +1726,7 @@ bool is_category_removable(const LLUUID& folder_id, bool check_worn)
         }
     }
 
-    const LLUUID mp_id = gInventory.findCategoryUUIDForType(LLFolderType::FT_MARKETPLACE_LISTINGS);
+    const LLUUID mp_id = gInventory.getMarketplaceListingsUUID();
     if (mp_id.notNull() && gInventory.isObjectDescendentOf(folder_id, mp_id))
     {
         return false;
@@ -1768,7 +1768,7 @@ void LLInventoryGallery::paste()
         return;
     }
 
-    const LLUUID& marketplacelistings_id = gInventory.findCategoryUUIDForType(LLFolderType::FT_MARKETPLACE_LISTINGS);
+    const LLUUID& marketplacelistings_id = gInventory.getMarketplaceListingsUUID();
     if (mSelectedItemIDs.size() == 1 && gInventory.isObjectDescendentOf(*mSelectedItemIDs.begin(), marketplacelistings_id))
     {
         return;
@@ -2120,7 +2120,7 @@ void LLInventoryGallery::pasteAsLink()
     }
 
     const LLUUID& current_outfit_id = gInventory.findCategoryUUIDForType(LLFolderType::FT_CURRENT_OUTFIT);
-    const LLUUID& marketplacelistings_id = gInventory.findCategoryUUIDForType(LLFolderType::FT_MARKETPLACE_LISTINGS);
+    const LLUUID& marketplacelistings_id = gInventory.getMarketplaceListingsUUID();
     const LLUUID& my_outifts_id = gInventory.findCategoryUUIDForType(LLFolderType::FT_MY_OUTFITS);
 
     std::vector<LLUUID> objects;
@@ -3339,7 +3339,7 @@ bool dragItemIntoFolder(LLUUID folder_id, LLInventoryItem* inv_item, bool drop,
     const LLUUID &current_outfit_id = model->findCategoryUUIDForType(LLFolderType::FT_CURRENT_OUTFIT);
     const LLUUID &favorites_id = model->findCategoryUUIDForType(LLFolderType::FT_FAVORITE);
     const LLUUID &landmarks_id = model->findCategoryUUIDForType(LLFolderType::FT_LANDMARK);
-    const LLUUID &marketplacelistings_id = model->findCategoryUUIDForType(LLFolderType::FT_MARKETPLACE_LISTINGS);
+    const LLUUID& marketplacelistings_id = model->getMarketplaceListingsUUID();
     const LLUUID &my_outifts_id = model->findCategoryUUIDForType(LLFolderType::FT_MY_OUTFITS);
 
     const bool move_is_into_current_outfit = (folder_id == current_outfit_id);
@@ -3733,7 +3733,7 @@ bool dragCategoryIntoFolder(LLUUID dest_id, LLInventoryCategory* inv_cat,
 
     const LLUUID &cat_id = inv_cat->getUUID();
     const LLUUID &current_outfit_id = model->findCategoryUUIDForType(LLFolderType::FT_CURRENT_OUTFIT);
-    const LLUUID &marketplacelistings_id = model->findCategoryUUIDForType(LLFolderType::FT_MARKETPLACE_LISTINGS);
+    const LLUUID& marketplacelistings_id = model->getMarketplaceListingsUUID();
     //const LLUUID from_folder_uuid = inv_cat->getParentUUID();
     const bool move_is_into_current_outfit = (dest_id == current_outfit_id);
     const bool move_is_into_marketplacelistings = model->isObjectDescendentOf(dest_id, marketplacelistings_id);
diff --git a/indra/newview/llinventorygallerymenu.cpp b/indra/newview/llinventorygallerymenu.cpp
index 7dce5d3952..037b82869e 100644
--- a/indra/newview/llinventorygallerymenu.cpp
+++ b/indra/newview/llinventorygallerymenu.cpp
@@ -412,7 +412,7 @@ void LLInventoryGalleryContextMenu::doToSelected(const LLSD& userdata)
 
         if (can_copy)
         {
-            const LLUUID& marketplacelistings_id = gInventory.findCategoryUUIDForType(LLFolderType::FT_MARKETPLACE_LISTINGS);
+            const LLUUID& marketplacelistings_id = gInventory.getMarketplaceListingsUUID();
             if (itemp)
             {
                 move_item_to_marketplacelistings(itemp, marketplacelistings_id, copy_operation);
@@ -431,7 +431,7 @@ void LLInventoryGalleryContextMenu::doToSelected(const LLSD& userdata)
                     // option == 0  Move no copy item(s)
                     // option == 1  Don't move no copy item(s) (leave them behind)
                     bool copy_and_move = option == 0;
-                    const LLUUID& marketplacelistings_id = gInventory.findCategoryUUIDForType(LLFolderType::FT_MARKETPLACE_LISTINGS);
+                    const LLUUID& marketplacelistings_id = gInventory.getMarketplaceListingsUUID();
 
                     // main inventory only allows one item?
                     LLViewerInventoryItem* itemp = gInventory.getItem(lamdba_list.front());
@@ -547,7 +547,7 @@ bool can_list_on_marketplace(const LLUUID &id)
         if (can_list)
         {
             std::string error_msg;
-            const LLUUID& marketplacelistings_id = gInventory.findCategoryUUIDForType(LLFolderType::FT_MARKETPLACE_LISTINGS);
+            const LLUUID& marketplacelistings_id = gInventory.getMarketplaceListingsUUID();
             if (marketplacelistings_id.notNull())
             {
                 LLViewerInventoryCategory* master_folder = gInventory.getCategory(marketplacelistings_id);
@@ -1045,7 +1045,7 @@ void LLInventoryGalleryContextMenu::updateMenuItemsVisibility(LLContextMenu* men
 
         // Marketplace
         bool can_list = false;
-        const LLUUID marketplacelistings_id = gInventory.findCategoryUUIDForType(LLFolderType::FT_MARKETPLACE_LISTINGS);
+        const LLUUID marketplacelistings_id = gInventory.getMarketplaceListingsUUID();
         if (marketplacelistings_id.notNull() && !is_inbox && !obj->getIsLinkType())
         {
             if (is_folder)
diff --git a/indra/newview/llinventorymodel.cpp b/indra/newview/llinventorymodel.cpp
index d100dcf051..9cc5f718f6 100644
--- a/indra/newview/llinventorymodel.cpp
+++ b/indra/newview/llinventorymodel.cpp
@@ -1043,6 +1043,15 @@ const LLUUID LLInventoryModel::findLibraryCategoryUUIDForType(LLFolderType::ETyp
     return findCategoryUUIDForTypeInRoot(preferred_type, gInventory.getLibraryRootFolderID());
 }
 
+const LLUUID LLInventoryModel::getMarketplaceListingsUUID()
+{
+    if (mMarketplaceListingsUUID.isNull())
+    {
+        mMarketplaceListingsUUID = findCategoryUUIDForType(LLFolderType::FT_MARKETPLACE_LISTINGS);
+    }
+    return mMarketplaceListingsUUID;
+}
+
 LLUUID LLInventoryModel::findCategoryByName(std::string_view name)
 {
     if (LLUUID root_id = gInventory.getRootFolderID(); root_id.notNull())
@@ -1842,7 +1851,7 @@ void LLInventoryModel::updateCategory(const LLViewerInventoryCategory* cat, U32
             mask |= LLInventoryObserver::LABEL;
         }
         // Under marketplace, category labels are quite complex and need extra upate
-        const LLUUID marketplace_id = findCategoryUUIDForType(LLFolderType::FT_MARKETPLACE_LISTINGS);
+        const LLUUID marketplace_id = getMarketplaceListingsUUID();
         if (marketplace_id.notNull() && isObjectDescendentOf(cat->getUUID(), marketplace_id))
         {
             mask |= LLInventoryObserver::LABEL;
diff --git a/indra/newview/llinventorymodel.h b/indra/newview/llinventorymodel.h
index 60254b15e7..6316c4f4c1 100644
--- a/indra/newview/llinventorymodel.h
+++ b/indra/newview/llinventorymodel.h
@@ -359,6 +359,8 @@ public:
     // user specified one or it does not exist, creates default category if it is missing.
     const LLUUID findUserDefinedCategoryUUIDForType(LLFolderType::EType preferred_type) const;
 
+    const LLUUID getMarketplaceListingsUUID();
+
     // Get whatever special folder this object is a child of, if any.
     const LLViewerInventoryCategory *getFirstNondefaultParent(const LLUUID& obj_id) const;
 
@@ -399,6 +401,8 @@ public:
 private:
     mutable LLPointer<LLViewerInventoryItem> mLastItem; // cache recent lookups
 
+    LLUUID mMarketplaceListingsUUID;
+
     // <FS:TT> ReplaceWornItemsOnly
     void wearWearablesOnAvatar(const LLUUID& category_id);
     void wearAttachmentsOnAvatar(const LLUUID& category_id);
diff --git a/indra/newview/llinventorymodelbackgroundfetch.cpp b/indra/newview/llinventorymodelbackgroundfetch.cpp
index 6906b2f9b0..0dcc447c3b 100644
--- a/indra/newview/llinventorymodelbackgroundfetch.cpp
+++ b/indra/newview/llinventorymodelbackgroundfetch.cpp
@@ -993,7 +993,7 @@ void LLInventoryModelBackgroundFetch::bulkFetchViaAis()
             // Intent is for marketplace request to happen after
             // main inventory is done, unless requested by floater
             mRecursiveMarketplaceFetchStarted = true;
-            const LLUUID& marketplacelistings_id = gInventory.findCategoryUUIDForType(LLFolderType::FT_MARKETPLACE_LISTINGS);
+            const LLUUID& marketplacelistings_id = gInventory.getMarketplaceListingsUUID();
             if (marketplacelistings_id.notNull())
             {
                 mFetchFolderQueue.emplace_front(marketplacelistings_id, FT_FOLDER_AND_CONTENT);
diff --git a/indra/newview/llmarketplacefunctions.cpp b/indra/newview/llmarketplacefunctions.cpp
index 98bfc91797..6ba4494cf6 100644
--- a/indra/newview/llmarketplacefunctions.cpp
+++ b/indra/newview/llmarketplacefunctions.cpp
@@ -851,7 +851,7 @@ void LLMarketplaceData::setDataFetchedSignal(const status_updated_signal_t::slot
 // Get/Post/Put requests to the SLM Server using the SLM API
 void LLMarketplaceData::getSLMListings()
 {
-    const LLUUID marketplaceFolderId = gInventory.findCategoryUUIDForType(LLFolderType::FT_MARKETPLACE_LISTINGS);
+    const LLUUID marketplaceFolderId = gInventory.getMarketplaceListingsUUID();
     setUpdating(marketplaceFolderId, true);
 
     LLCoros::instance().launch("getSLMListings",
@@ -1758,7 +1758,7 @@ bool LLMarketplaceData::isUpdating(const LLUUID& folder_id, S32 depth)
     }
     else
     {
-        const LLUUID marketplace_listings_uuid = gInventory.findCategoryUUIDForType(LLFolderType::FT_MARKETPLACE_LISTINGS);
+        const LLUUID marketplace_listings_uuid = gInventory.getMarketplaceListingsUUID();
         std::set<LLUUID>::iterator it = mPendingUpdateSet.find(marketplace_listings_uuid);
         if (it != mPendingUpdateSet.end())
         {
diff --git a/indra/newview/llpanellogin.cpp b/indra/newview/llpanellogin.cpp
index 23de79c4c6..e01afa9e8f 100644
--- a/indra/newview/llpanellogin.cpp
+++ b/indra/newview/llpanellogin.cpp
@@ -190,7 +190,8 @@ LLPanelLogin::LLPanelLogin(const LLRect &rect,
     mUsernameLength(0),
     mPasswordLength(0),
     mLocationLength(0),
-    mShowFavorites(false)
+    mShowFavorites(false),
+    mAlertNotif(false)
 {
     setBackgroundVisible(false);
     setBackgroundOpaque(true);
@@ -299,8 +300,8 @@ LLPanelLogin::LLPanelLogin(const LLRect &rect,
 
     childSetAction("connect_btn", onClickConnect, this);
 
-    LLButton* def_btn = getChild<LLButton>("connect_btn");
-    setDefaultBtn(def_btn);
+    mLoginBtn = getChild<LLButton>("connect_btn");
+    setDefaultBtn(mLoginBtn);
 
     std::string channel = LLVersionInfo::instance().getChannel();
     std::string version = stringize(LLVersionInfo::instance().getShortVersion(), " (",
@@ -329,6 +330,8 @@ LLPanelLogin::LLPanelLogin(const LLRect &rect,
     LLCheckBoxCtrl* remember_name = getChild<LLCheckBoxCtrl>("remember_name");
     remember_name->setCommitCallback(boost::bind(&LLPanelLogin::onRememberUserCheck, this));
     getChild<LLCheckBoxCtrl>("remember_password")->setCommitCallback(boost::bind(&LLPanelLogin::onRememberPasswordCheck, this));
+
+    mAlertListener = LLNotifications::instance().getChannel("Alerts")->connectChanged([this](const LLSD& notify){ return onUpdateNotification(notify); });
 }
 
 void LLPanelLogin::addFavoritesToStartLocation()
@@ -411,7 +414,7 @@ void LLPanelLogin::addFavoritesToStartLocation()
                 gSavedSettings.setBOOL("RememberPassword", save_password);
                 if (!save_password)
                 {
-                    getChild<LLButton>("connect_btn")->setEnabled(false);
+                    mLoginBtn->setEnabled(false);
                 }
                 update_password_setting = false;
             }
@@ -938,7 +941,7 @@ void LLPanelLogin::handleMediaEvent(LLPluginClassMedia* /*self*/, EMediaEvent ev
 // static
 void LLPanelLogin::onClickConnect(bool commit_fields)
 {
-    if (sInstance && sInstance->mCallback)
+    if (sInstance && sInstance->mCallback && !sInstance->mAlertNotif)
     {
         if (commit_fields)
         {
@@ -1195,9 +1198,7 @@ void LLPanelLogin::updateServer()
 
 void LLPanelLogin::updateLoginButtons()
 {
-    LLButton* login_btn = getChild<LLButton>("connect_btn");
-
-    login_btn->setEnabled(mUsernameLength != 0 && mPasswordLength != 0);
+    mLoginBtn->setEnabled(mUsernameLength != 0 && mPasswordLength != 0 && !mAlertNotif);
 
     if (!mFirstLoginThisInstall)
     {
@@ -1368,4 +1369,24 @@ std::string LLPanelLogin::getUserName(LLPointer<LLCredential> &cred)
 
     return "unknown";
 }
+
+bool LLPanelLogin::onUpdateNotification(const LLSD& notify)
+{
+    // disable Login button while alert notification is displayed
+    LLNotificationPtr notifyp = LLNotifications::instance().find(notify["id"].asUUID());
+    if (notifyp && notifyp->getName() == "PromptOptionalUpdate")
+    {
+        std::string sigtype = notify["sigtype"].asString();
+        if (sigtype == "add")
+        {
+            mAlertNotif = true;
+        }
+        else if (sigtype == "delete")
+        {
+            mAlertNotif = false;
+        }
+        updateLoginButtons();
+    }
+    return false;
+}
 #endif
diff --git a/indra/newview/llpanellogin.h b/indra/newview/llpanellogin.h
index c1319bde2c..cc68146b07 100644
--- a/indra/newview/llpanellogin.h
+++ b/indra/newview/llpanellogin.h
@@ -107,8 +107,11 @@ private:
     static void onRememberPasswordCheck(void*);
     static void onPassKey(LLLineEditor* caller, void* user_data);
 
+    bool onUpdateNotification(const LLSD& notify);
+
 private:
     std::unique_ptr<LLPanelLoginListener> mListener;
+    LLTempBoundListener mAlertListener;
 
     void updateLoginButtons();
     void populateUserList(LLPointer<LLCredential> credential);
@@ -128,6 +131,9 @@ private:
     unsigned int mUsernameLength;
     unsigned int mPasswordLength;
     unsigned int mLocationLength;
+
+    bool mAlertNotif;
+    LLButton* mLoginBtn;
 };
 
 #endif
diff --git a/indra/newview/lltooldraganddrop.cpp b/indra/newview/lltooldraganddrop.cpp
index 531d942573..c2bb754bcb 100644
--- a/indra/newview/lltooldraganddrop.cpp
+++ b/indra/newview/lltooldraganddrop.cpp
@@ -789,7 +789,7 @@ void LLToolDragAndDrop::dragOrDrop( S32 x, S32 y, MASK mask, bool drop,
     if (!handled)
     {
         // Disallow drag and drop to 3D from the marketplace
-        const LLUUID marketplacelistings_id = gInventory.findCategoryUUIDForType(LLFolderType::FT_MARKETPLACE_LISTINGS);
+        const LLUUID marketplacelistings_id = gInventory.getMarketplaceListingsUUID();
         if (marketplacelistings_id.notNull())
         {
             for (S32 item_index = 0; item_index < (S32)mCargoIDs.size(); item_index++)
diff --git a/indra/newview/llviewermenu.cpp b/indra/newview/llviewermenu.cpp
index 8612fcefa7..07311d692c 100644
--- a/indra/newview/llviewermenu.cpp
+++ b/indra/newview/llviewermenu.cpp
@@ -506,7 +506,7 @@ void LLSLMMenuUpdater::setMerchantMenu()
     LLCommand* command = LLCommandManager::instance().getCommand("marketplacelistings");
     gToolBarView->enableCommand(command->id(), true);
 
-    const LLUUID marketplacelistings_id = gInventory.findCategoryUUIDForType(LLFolderType::FT_MARKETPLACE_LISTINGS);
+    const LLUUID marketplacelistings_id = gInventory.getMarketplaceListingsUUID();
     if (marketplacelistings_id.isNull())
     {
         U32 mkt_status = LLMarketplaceData::instance().getSLMStatus();
diff --git a/indra/newview/quickprefs.cpp b/indra/newview/quickprefs.cpp
index 6f37dacfbc..8d408433e4 100644
--- a/indra/newview/quickprefs.cpp
+++ b/indra/newview/quickprefs.cpp
@@ -63,10 +63,10 @@ class FSSettingsCollector : public LLInventoryCollectFunctor
 public:
     FSSettingsCollector()
     {
-        mMarketplaceFolderUUID = gInventory.findCategoryUUIDForType(LLFolderType::FT_MARKETPLACE_LISTINGS);
+        mMarketplaceFolderUUID = gInventory.getMarketplaceListingsUUID();
     }
 
-    virtual ~FSSettingsCollector() {}
+    virtual ~FSSettingsCollector() = default;
 
     bool operator()(LLInventoryCategory* cat, LLInventoryItem* item)
     {
@@ -85,7 +85,7 @@ public:
 
 protected:
     LLUUID mMarketplaceFolderUUID;
-    std::set<LLUUID> mSeen;
+    uuid_set_t mSeen;
 };
 
 
diff --git a/indra/newview/skins/default/xui/en/notifications.xml b/indra/newview/skins/default/xui/en/notifications.xml
index 24c46de31f..65210e1480 100644
--- a/indra/newview/skins/default/xui/en/notifications.xml
+++ b/indra/newview/skins/default/xui/en/notifications.xml
@@ -4555,9 +4555,9 @@ Click OK to install.
   </notification>
 
   <notification
-   icon="alertmodal.tga"
+   icon="alert.tga"
    name="PromptOptionalUpdate"
-   type="alertmodal">
+   type="alert">
 Version [VERSION] has been downloaded and is ready to install.
 Release notes: [URL]
 
diff --git a/indra/newview/skins/default/xui/en/panel_preferences_general.xml b/indra/newview/skins/default/xui/en/panel_preferences_general.xml
index 7286ea146b..34c22f3c11 100644
--- a/indra/newview/skins/default/xui/en/panel_preferences_general.xml
+++ b/indra/newview/skins/default/xui/en/panel_preferences_general.xml
@@ -139,7 +139,7 @@
      width="70">
         <combo_box.item
          enabled="true"
-         label="1:00 AM"
+         label="1:00 PM"
          name="12H"
          value="0" />
         <combo_box.item