diff --git a/Source/Core/DolphinQt/CMakeLists.txt b/Source/Core/DolphinQt/CMakeLists.txt
index 0e08a4ed98..1c02e783bb 100644
--- a/Source/Core/DolphinQt/CMakeLists.txt
+++ b/Source/Core/DolphinQt/CMakeLists.txt
@@ -396,6 +396,9 @@ if (MSVC)
   target_compile_options(dolphin-emu PRIVATE "${qtGuiPriv}")
   target_compile_options(dolphin-emu PRIVATE "${qtWidgets}")
 
+  # Qt 6.3.0 headers use std::aligned_storage instead of alignas
+  target_compile_definitions(dolphin-emu PRIVATE _SILENCE_CXX23_ALIGNED_STORAGE_DEPRECATION_WARNING)
+
   if ("${QT_VERSION_MAJOR}" GREATER_EQUAL 6)
     # Qt6 requires RTTI
     remove_cxx_flag_from_target(dolphin-emu "/GR-")
diff --git a/Source/Core/DolphinQt/DolphinQt.vcxproj b/Source/Core/DolphinQt/DolphinQt.vcxproj
index cde2161e7b..e9630614b6 100644
--- a/Source/Core/DolphinQt/DolphinQt.vcxproj
+++ b/Source/Core/DolphinQt/DolphinQt.vcxproj
@@ -31,6 +31,9 @@
       <AdditionalIncludeDirectories>$(ProjectDir)TAS;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
       <AdditionalIncludeDirectories>$(ProjectDir)VideoInterface;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
 
+      <!--Qt 6.3.0 headers use std::aligned_storage instead of alignas-->
+      <PreprocessorDefinitions>_SILENCE_CXX23_ALIGNED_STORAGE_DEPRECATION_WARNING;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+
       <!--Jump through some hoops to generate a pch file local to this project-->
       <AdditionalIncludeDirectories>$(SourceDir)PCH;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
       <PrecompiledHeader>Use</PrecompiledHeader>
diff --git a/Source/Core/DolphinQt/MainWindow.h b/Source/Core/DolphinQt/MainWindow.h
index 6e53f2df10..5f9eb34bb2 100644
--- a/Source/Core/DolphinQt/MainWindow.h
+++ b/Source/Core/DolphinQt/MainWindow.h
@@ -11,11 +11,12 @@
 #include <optional>
 #include <string>
 
+#include "Core/Boot/Boot.h"
+
 class QStackedWidget;
 class QString;
 
 class BreakpointWidget;
-class BootSessionData;
 struct BootParameters;
 class CheatsManager;
 class CodeWidget;