diff --git a/Common/Data/Collections/FastVec.h b/Common/Data/Collections/FastVec.h
index 08e5176d4a..6622cbdeb8 100644
--- a/Common/Data/Collections/FastVec.h
+++ b/Common/Data/Collections/FastVec.h
@@ -69,7 +69,8 @@ public:
 	void clear() { size_ = 0; }
 	bool empty() const { return size_ == 0; }
 
-	const T *data() { return data_; }
+	const T *data() const { return data_; }
+
 	T *begin() { return data_; }
 	T *end() { return data_ + size_; }
 	const T *begin() const { return data_; }
diff --git a/Common/Data/Collections/TinySet.h b/Common/Data/Collections/TinySet.h
index 6521beab48..04911fddce 100644
--- a/Common/Data/Collections/TinySet.h
+++ b/Common/Data/Collections/TinySet.h
@@ -2,6 +2,8 @@
 
 #include <vector>
 
+#include "Common/Log.h"
+
 // Insert-only small-set implementation. Performs no allocation unless MaxFastSize is exceeded.
 // Can also be used as a small vector, then use push_back (or push_in_place) instead of insert.
 // Duplicates are thus allowed if you use that, but not if you exclusively use insert.
@@ -32,16 +34,18 @@ struct TinySet {
 		}
 		slowLookup_->push_back(t);
 	}
-	inline T *add_back() {
+	inline T &push_uninitialized() {
 		if (fastCount_ < MaxFastSize) {
-			return &fastLookup_[fastCount_++];
+			return fastLookup_[fastCount_++];
 		}
 		if (!slowLookup_) {
 			slowLookup_ = new std::vector<T>();
 		}
+
+		// The slow lookup is also slow at adding.
 		T t;
 		slowLookup_->push_back(t);
-		return slowLookup_->back();
+		return *slowLookup_->back();
 	}
 	void append(const TinySet<T, MaxFastSize> &other) {
 		size_t otherSize = other.size();
@@ -136,8 +140,8 @@ private:
 };
 
 template <class T, int MaxSize>
-struct FixedTinyVec {
-	~FixedTinyVec() {}
+struct FixedVec {
+	~FixedVec() {}
 	// WARNING: Can fail if you exceed MaxSize!
 	inline bool push_back(const T &t) {
 		if (count_ < MaxSize) {
@@ -147,13 +151,16 @@ struct FixedTinyVec {
 			return false;
 		}
 	}
+
 	// WARNING: Can fail if you exceed MaxSize!
-	inline T *add_back() {
+	inline T &push_uninitialized() {
 		if (count_ < MaxSize) {
 			return &data_[count_++];
 		}
-		return nullptr;
+		_dbg_assert_(false);
+		return *data_[MaxSize - 1];  // BAD
 	}
+
 	// Invalid if empty().
 	void pop_back() { count_--;	}
 
@@ -184,7 +191,7 @@ struct FixedTinyVec {
 	const T &back() const { return (*this)[size() - 1]; }
 	const T &front() const { return (*this)[0]; }
 
-	bool operator == (const FixedTinyVec<T, MaxSize> &other) const {
+	bool operator == (const FixedVec<T, MaxSize> &other) const {
 		if (count_ != other.count_)
 			return false;
 		for (int i = 0; i < count_; i++) {
diff --git a/Common/GPU/Vulkan/VulkanBarrier.h b/Common/GPU/Vulkan/VulkanBarrier.h
index 1fefb5adfa..9382f71166 100644
--- a/Common/GPU/Vulkan/VulkanBarrier.h
+++ b/Common/GPU/Vulkan/VulkanBarrier.h
@@ -5,6 +5,7 @@
 
 #include "Common/Log.h"
 #include "Common/GPU/Vulkan/VulkanLoader.h"
+#include "Common/Data/Collections/FastVec.h"
 
 class VulkanContext;
 
@@ -13,6 +14,8 @@ class VulkanContext;
 // However, not thread safe in any way!
 class VulkanBarrier {
 public:
+	VulkanBarrier() : imageBarriers_(4) {}
+
 	void TransitionImage(
 		VkImage image, int baseMip, int numMipLevels, int numLayers, VkImageAspectFlags aspectMask,
 		VkImageLayout oldImageLayout, VkImageLayout newImageLayout,
@@ -25,7 +28,7 @@ public:
 		dstStageMask_ |= dstStageMask;
 		dependencyFlags_ |= VK_DEPENDENCY_BY_REGION_BIT;
 
-		VkImageMemoryBarrier imageBarrier;
+		VkImageMemoryBarrier &imageBarrier = imageBarriers_.push_uninitialized();
 		imageBarrier.sType = VK_STRUCTURE_TYPE_IMAGE_MEMORY_BARRIER;
 		imageBarrier.pNext = nullptr;
 		imageBarrier.srcAccessMask = srcAccessMask;
@@ -40,7 +43,6 @@ public:
 		imageBarrier.subresourceRange.baseArrayLayer = 0;
 		imageBarrier.srcQueueFamilyIndex = VK_QUEUE_FAMILY_IGNORED;
 		imageBarrier.dstQueueFamilyIndex = VK_QUEUE_FAMILY_IGNORED;
-		imageBarriers_.push_back(imageBarrier);
 	}
 
 	// Automatically determines access and stage masks from layouts.
@@ -93,7 +95,7 @@ public:
 			break;
 		}
 
-		VkImageMemoryBarrier imageBarrier;
+		VkImageMemoryBarrier &imageBarrier = imageBarriers_.push_uninitialized();
 		imageBarrier.sType = VK_STRUCTURE_TYPE_IMAGE_MEMORY_BARRIER;
 		imageBarrier.pNext = nullptr;
 		imageBarrier.srcAccessMask = srcAccessMask;
@@ -108,7 +110,6 @@ public:
 		imageBarrier.subresourceRange.baseArrayLayer = 0;
 		imageBarrier.srcQueueFamilyIndex = VK_QUEUE_FAMILY_IGNORED;
 		imageBarrier.dstQueueFamilyIndex = VK_QUEUE_FAMILY_IGNORED;
-		imageBarriers_.push_back(imageBarrier);
 	}
 
 	void Flush(VkCommandBuffer cmd);
@@ -116,6 +117,6 @@ public:
 private:
 	VkPipelineStageFlags srcStageMask_ = 0;
 	VkPipelineStageFlags dstStageMask_ = 0;
-	std::vector<VkImageMemoryBarrier> imageBarriers_;
+	FastVec<VkImageMemoryBarrier> imageBarriers_;
 	VkDependencyFlags dependencyFlags_ = 0;
 };
diff --git a/Common/System/System.h b/Common/System/System.h
index 48cfaa280a..1568e43ed5 100644
--- a/Common/System/System.h
+++ b/Common/System/System.h
@@ -188,6 +188,8 @@ enum SystemProperty {
 	SYSPROP_SKIP_UI,
 
 	SYSPROP_USER_DOCUMENTS_DIR,
+
+	SYSPROP_OK_BUTTON_LEFT,
 };
 
 enum class SystemNotification {
diff --git a/Common/UI/UIScreen.cpp b/Common/UI/UIScreen.cpp
index 94c3c420f7..c49dee977c 100644
--- a/Common/UI/UIScreen.cpp
+++ b/Common/UI/UIScreen.cpp
@@ -1,6 +1,9 @@
 #include <algorithm>
+
+#include "Common/Log.h"
 #include "Common/System/Display.h"
 #include "Common/System/System.h"
+#include "Common/System/Request.h"
 #include "Common/Input/InputState.h"
 #include "Common/Input/KeyCodes.h"
 #include "Common/Math/curves.h"
@@ -10,8 +13,6 @@
 #include "Common/UI/Root.h"
 #include "Common/Data/Text/I18n.h"
 #include "Common/Render/DrawBuffer.h"
-#include "Common/Log.h"
-#include <Common/System/Request.h>
 
 static const bool ClickDebug = false;
 
@@ -393,10 +394,8 @@ void PopupScreen::TriggerFinish(DialogResult result) {
 
 		OnCompleted(result);
 	}
-#if PPSSPP_PLATFORM(UWP)
 	// Inform UI that popup close to hide OSK (if visible)
 	System_NotifyUIState("popup_closed");
-#endif
 }
 
 void PopupScreen::CreateViews() {
@@ -433,17 +432,17 @@ void PopupScreen::CreateViews() {
 		Margins buttonMargins(5, 5);
 
 		// Adjust button order to the platform default.
-#if defined(_WIN32)
-		defaultButton_ = buttonRow->Add(new Button(button1_, new LinearLayoutParams(1.0f, buttonMargins)));
-		defaultButton_->OnClick.Handle<UIScreen>(this, &UIScreen::OnOK);
-		if (!button2_.empty())
-			buttonRow->Add(new Button(button2_, new LinearLayoutParams(1.0f, buttonMargins)))->OnClick.Handle<UIScreen>(this, &UIScreen::OnCancel);
-#else
-		if (!button2_.empty())
-			buttonRow->Add(new Button(button2_, new LinearLayoutParams(1.0f)))->OnClick.Handle<UIScreen>(this, &UIScreen::OnCancel);
-		defaultButton_ = buttonRow->Add(new Button(button1_, new LinearLayoutParams(1.0f)));
-		defaultButton_->OnClick.Handle<UIScreen>(this, &UIScreen::OnOK);
-#endif
+		if (System_GetPropertyBool(SYSPROP_OK_BUTTON_LEFT)) {
+			defaultButton_ = buttonRow->Add(new Button(button1_, new LinearLayoutParams(1.0f, buttonMargins)));
+			defaultButton_->OnClick.Handle<UIScreen>(this, &UIScreen::OnOK);
+			if (!button2_.empty())
+				buttonRow->Add(new Button(button2_, new LinearLayoutParams(1.0f, buttonMargins)))->OnClick.Handle<UIScreen>(this, &UIScreen::OnCancel);
+		} else {
+			if (!button2_.empty())
+				buttonRow->Add(new Button(button2_, new LinearLayoutParams(1.0f)))->OnClick.Handle<UIScreen>(this, &UIScreen::OnCancel);
+			defaultButton_ = buttonRow->Add(new Button(button1_, new LinearLayoutParams(1.0f)));
+			defaultButton_->OnClick.Handle<UIScreen>(this, &UIScreen::OnOK);
+		}
 
 		box_->Add(buttonRow);
 	}
diff --git a/Core/Config.cpp b/Core/Config.cpp
index a5dcc32f35..22e1a7d86f 100644
--- a/Core/Config.cpp
+++ b/Core/Config.cpp
@@ -184,7 +184,7 @@ static bool DefaultVSync() {
 }
 
 static bool DefaultEnableStateUndo() {
-#ifdef MOBILE_DEVICE
+#ifdef PPSSPP_PLATFORM(ANDROID) || PPSSPP_PLATFORM(IOS)
 	// Off on mobile to save disk space.
 	return false;
 #endif
diff --git a/Core/HLE/sceKernelModule.cpp b/Core/HLE/sceKernelModule.cpp
index cbb81ed098..87cf486f4a 100644
--- a/Core/HLE/sceKernelModule.cpp
+++ b/Core/HLE/sceKernelModule.cpp
@@ -1405,10 +1405,6 @@ static PSPModule *__KernelLoadELFFromPtr(const u8 *ptr, size_t elfSize, u32 load
 
 	if (!module->isFake) {
 		bool scan = true;
-#if defined(MOBILE_DEVICE)
-		scan = g_Config.bFuncReplacements;
-#endif
-
 		// If the ELF has debug symbols, don't add entries to the symbol table.
 		bool insertSymbols = scan && !reader.LoadSymbols();
 		std::vector<SectionID> codeSections = reader.GetCodeSections();
diff --git a/Core/KeyMap.cpp b/Core/KeyMap.cpp
index 7d46dfb515..5a9235d620 100644
--- a/Core/KeyMap.cpp
+++ b/Core/KeyMap.cpp
@@ -408,8 +408,8 @@ const KeyMap_IntStrPair psp_button_names[] = {
 	{VIRTKEY_SPEED_CUSTOM2, "Alt speed 2"},
 	{VIRTKEY_SPEED_ANALOG, "Analog speed"},
 	{VIRTKEY_PAUSE, "Pause"},
-#ifndef MOBILE_DEVICE
 	{VIRTKEY_FRAME_ADVANCE, "Frame Advance"},
+#if !defined(MOBILE_DEVICE)
 	{VIRTKEY_RECORD, "Audio/Video Recording" },
 #endif
 	{VIRTKEY_REWIND, "Rewind"},
diff --git a/Core/KeyMap.h b/Core/KeyMap.h
index 3459433b2d..976ed67e06 100644
--- a/Core/KeyMap.h
+++ b/Core/KeyMap.h
@@ -148,7 +148,7 @@ namespace KeyMap {
 			return false;
 		}
 
-		FixedTinyVec<InputMapping, 3> mappings;
+		FixedVec<InputMapping, 3> mappings;
 	};
 
 	typedef std::map<int, std::vector<MultiInputMapping>> KeyMapping;
diff --git a/Core/System.cpp b/Core/System.cpp
index 0c7bf42fb4..8421cb297e 100644
--- a/Core/System.cpp
+++ b/Core/System.cpp
@@ -566,11 +566,9 @@ void PSP_Shutdown() {
 	if (coreState == CORE_RUNNING)
 		Core_Stop();
 
-#ifndef MOBILE_DEVICE
 	if (g_Config.bFuncHashMap) {
 		MIPSAnalyst::StoreHashMap();
 	}
-#endif
 
 	if (pspIsIniting)
 		Core_NotifyLifecycle(CoreLifecycle::START_COMPLETE);
diff --git a/UWP/PPSSPP_UWPMain.cpp b/UWP/PPSSPP_UWPMain.cpp
index 52e1b37aca..b3a9ff0a4b 100644
--- a/UWP/PPSSPP_UWPMain.cpp
+++ b/UWP/PPSSPP_UWPMain.cpp
@@ -435,6 +435,8 @@ bool System_GetPropertyBool(SystemProperty prop) {
 	}
 	case SYSPROP_DEBUGGER_PRESENT:
 		return IsDebuggerPresent();
+	case SYSPROP_OK_BUTTON_LEFT:
+		return true;
 	default:
 		return false;
 	}
diff --git a/Windows/main.cpp b/Windows/main.cpp
index 762d5a747e..05dd0b6018 100644
--- a/Windows/main.cpp
+++ b/Windows/main.cpp
@@ -383,6 +383,8 @@ bool System_GetPropertyBool(SystemProperty prop) {
 		return !g_Config.bDisableHTTPS;
 	case SYSPROP_DEBUGGER_PRESENT:
 		return IsDebuggerPresent();
+	case SYSPROP_OK_BUTTON_LEFT:
+		return true;
 	default:
 		return false;
 	}