diff --git a/qt/src/EmuApplication.cpp b/qt/src/EmuApplication.cpp
index 4d27929b..cdcdba26 100644
--- a/qt/src/EmuApplication.cpp
+++ b/qt/src/EmuApplication.cpp
@@ -240,7 +240,7 @@ void EmuApplication::startThread()
     }
 }
 
-bool EmuApplication::openFile(std::string filename)
+bool EmuApplication::openFile(const std::string &filename)
 {
     window->gameChanging();
     updateSettings();
@@ -428,7 +428,7 @@ void EmuApplication::updateSettings()
 
 void EmuApplication::pollJoysticks()
 {
-    while (1)
+    while (true)
     {
         auto event = input_manager->processEvent();
         if (!event)
@@ -436,6 +436,8 @@ void EmuApplication::pollJoysticks()
 
         switch (event->type)
         {
+        default:
+            break;
         case SDL_EVENT_JOYSTICK_ADDED:
         case SDL_EVENT_JOYSTICK_REMOVED:
             if (joypads_changed_callback)
@@ -506,7 +508,7 @@ void EmuApplication::loadState(int slot)
     });
 }
 
-void EmuApplication::loadState(std::string filename)
+void EmuApplication::loadState(const std::string& filename)
 {
     emu_thread->runOnThread([&, filename] {
         core->loadState(filename);
@@ -520,7 +522,7 @@ void EmuApplication::saveState(int slot)
     });
 }
 
-void EmuApplication::saveState(std::string filename)
+void EmuApplication::saveState(const std::string& filename)
 {
     emu_thread->runOnThread([&, filename] {
         core->saveState(filename);
@@ -583,7 +585,8 @@ void EmuApplication::disableCheat(int index)
     });
 }
 
-bool EmuApplication::addCheat(std::string description, std::string code)
+bool EmuApplication::addCheat(const std::string &description,
+                              const std::string &code)
 {
     suspendThread();
     auto retval = core->addCheat(description, code);
@@ -605,7 +608,7 @@ void EmuApplication::deleteAllCheats()
     });
 }
 
-int EmuApplication::tryImportCheats(std::string filename)
+int EmuApplication::tryImportCheats(const std::string &filename)
 {
     suspendThread();
     auto retval = core->tryImportCheats(filename);
@@ -613,7 +616,7 @@ int EmuApplication::tryImportCheats(std::string filename)
     return retval;
 }
 
-std::string EmuApplication::validateCheat(std::string code)
+std::string EmuApplication::validateCheat(const std::string &code)
 {
     suspendThread();
     auto retval = core->validateCheat(code);
@@ -621,7 +624,8 @@ std::string EmuApplication::validateCheat(std::string code)
     return retval;
 }
 
-int EmuApplication::modifyCheat(int index, std::string name, std::string code)
+int EmuApplication::modifyCheat(int index, const std::string &name,
+                                const std::string &code)
 {
     suspendThread();
     auto retval = core->modifyCheat(index, name, code);
@@ -651,7 +655,7 @@ std::string EmuApplication::getContentFolder()
     return core->getContentFolder();
 }
 
-void EmuThread::runOnThread(std::function<void()> func, bool blocking)
+void EmuThread::runOnThread(const std::function<void()> &func, bool blocking)
 {
     if (QThread::currentThread() != this)
     {
@@ -667,7 +671,7 @@ void EmuThread::runOnThread(std::function<void()> func, bool blocking)
 }
 
 EmuThread::EmuThread(QThread *main_thread_)
-    : main_thread(main_thread_), QThread()
+    : QThread(), main_thread(main_thread_)
 {
     qRegisterMetaType<std::function<void()>>("std::function<void()>");
 }
@@ -687,7 +691,7 @@ void EmuThread::waitForStatusBit(int new_status)
     if (status & new_status)
         return;
 
-    while (1)
+    while (true)
     {
         QThread::yieldCurrentThread();
         if (status & new_status)
@@ -700,7 +704,7 @@ void EmuThread::waitForStatusBitCleared(int new_status)
     if (!(status & new_status))
         return;
 
-    while (1)
+    while (true)
     {
         QThread::yieldCurrentThread();
         if (!(status & new_status))
@@ -720,11 +724,11 @@ void EmuThread::unpause()
 
 void EmuThread::run()
 {
-    auto event_loop = new QEventLoop();
+    auto event_loop = std::make_unique<QEventLoop>();
 
     setStatusBits(ePaused);
 
-    while (1)
+    while (true)
     {
         event_loop->processEvents();
 
@@ -742,7 +746,7 @@ void EmuThread::run()
     }
 }
 
-void EmuThread::setMainLoop(std::function<void ()> loop)
+void EmuThread::setMainLoop(const std::function<void()> &loop)
 {
     main_loop = loop;
 }
diff --git a/qt/src/EmuApplication.hpp b/qt/src/EmuApplication.hpp
index 0936fb82..bee02004 100644
--- a/qt/src/EmuApplication.hpp
+++ b/qt/src/EmuApplication.hpp
@@ -23,7 +23,7 @@ Q_OBJECT
     void unsetStatusBits(int);
     void pause();
     void unpause();
-    void setMainLoop(std::function<void()> loop);
+    void setMainLoop(const std::function<void()> &loop);
 
     std::function<void()> main_loop = nullptr;
 
@@ -39,7 +39,7 @@ Q_OBJECT
     int status = eDead;
 
   public slots:
-    void runOnThread(std::function<void()> func, bool blocking = false);
+    void runOnThread(const std::function<void()> &func, bool blocking = false);
 };
 
 struct EmuApplication
@@ -54,7 +54,7 @@ struct EmuApplication
 
     EmuApplication();
     ~EmuApplication();
-    bool openFile(std::string filename);
+    bool openFile(const std::string &filename);
     void handleBinding(std::string name, bool pressed);
     void updateSettings();
     void updateBindings();
@@ -75,9 +75,9 @@ struct EmuApplication
     bool isPaused();
     void unpause();
     void loadState(int slot);
-    void loadState(std::string filename);
+    void loadState(const std::string& filename);
     void saveState(int slot);
-    void saveState(std::string filename);
+    void saveState(const std::string& filename);
     std::string getStateFolder();
     void loadUndoState();
     void startGame();
@@ -91,12 +91,13 @@ struct EmuApplication
     void disableAllCheats();
     void enableCheat(int index);
     void disableCheat(int index);
-    bool addCheat(std::string description, std::string code);
+    bool addCheat(const std::string &description, const std::string &code);
     void deleteCheat(int index);
     void deleteAllCheats();
-    int tryImportCheats(std::string filename);
-    std::string validateCheat(std::string code);
-    int modifyCheat(int index, std::string name, std::string code);
+    int tryImportCheats(const std::string &filename);
+    std::string validateCheat(const std::string &code);
+    int modifyCheat(int index, const std::string &name,
+                    const std::string &code);
 
     enum Handler
     {
diff --git a/qt/src/EmuMainWindow.cpp b/qt/src/EmuMainWindow.cpp
index 1e063a40..c35f5345 100644
--- a/qt/src/EmuMainWindow.cpp
+++ b/qt/src/EmuMainWindow.cpp
@@ -2,11 +2,8 @@
 #include <QMenu>
 #include <QMenuBar>
 #include <QFileDialog>
-#include <QtWidgets>
 #include <QtEvents>
 #include <QGuiApplication>
-#include <QStackedWidget>
-#include <qguiapplication.h>
 #include <qnamespace.h>
 #include <qpa/qplatformnativeinterface.h>
 
@@ -14,14 +11,16 @@
 #include <dwmapi.h>
 #endif
 
-#include "EmuMainWindow.hpp"
-#include "EmuSettingsWindow.hpp"
+#include "CheatsDialog.hpp"
 #include "EmuApplication.hpp"
 #include "EmuBinding.hpp"
-#include "EmuCanvasVulkan.hpp"
 #include "EmuCanvasOpenGL.hpp"
 #include "EmuCanvasQt.hpp"
-#include "CheatsDialog.hpp"
+#include "EmuCanvasVulkan.hpp"
+#include "EmuMainWindow.hpp"
+#include "EmuSettingsWindow.hpp"
+
+#include <QMessageBox>
 #undef KeyPress
 
 static EmuSettingsWindow *g_emu_settings_window = nullptr;
@@ -30,7 +29,7 @@ class DefaultBackground
     : public QWidget
 {
 public:
-    DefaultBackground(QWidget *parent)
+    explicit DefaultBackground(QWidget *parent)
         : QWidget(parent)
     {
     }
@@ -67,9 +66,7 @@ EmuMainWindow::EmuMainWindow(EmuApplication *app)
     });
 }
 
-EmuMainWindow::~EmuMainWindow()
-{
-}
+EmuMainWindow::~EmuMainWindow() = default;
 
 void EmuMainWindow::destroyCanvas()
 {
@@ -80,8 +77,7 @@ void EmuMainWindow::destroyCanvas()
     if (using_stacked_widget)
     {
         auto stackwidget = (QStackedWidget *)central_widget;
-        EmuCanvas *widget = (EmuCanvas *)stackwidget->widget(0);
-        if (widget)
+        if (auto widget = (EmuCanvas *)stackwidget->widget(0))
         {
             widget->deinit();
             stackwidget->removeWidget(widget);
@@ -91,7 +87,7 @@ void EmuMainWindow::destroyCanvas()
     }
     else
     {
-        EmuCanvas *widget = (EmuCanvas *)takeCentralWidget();
+        auto widget = (EmuCanvas *)takeCentralWidget();
         widget->deinit();
         delete widget;
     }
@@ -174,7 +170,7 @@ void EmuMainWindow::createWidgets()
     // File menu
     auto file_menu = new QMenu(tr("&File"));
     auto open_item = file_menu->addAction(QIcon(iconset + "open.svg"), tr("&Open File..."));
-    open_item->connect(open_item, &QAction::triggered, this, [&] {
+    connect(open_item, &QAction::triggered, this, [&] {
         openFile();
     });
     // File->Recent Files submenu
@@ -229,7 +225,7 @@ void EmuMainWindow::createWidgets()
     file_menu->addMenu(save_state_menu);
 
     auto exit_item = new QAction(QIcon(iconset + "exit.svg"), tr("E&xit"));
-    exit_item->connect(exit_item, &QAction::triggered, this, [&](bool checked) {
+    connect(exit_item, &QAction::triggered, this, [&](bool checked) {
         close();
     });
 
@@ -304,7 +300,7 @@ void EmuMainWindow::createWidgets()
     {
         auto string = (i == 10) ? tr("1&0x") : tr("&%1x").arg(i);
         auto item = set_size_menu->addAction(string);
-        item->connect(item, &QAction::triggered, this, [&, i](bool checked) {
+        connect(item, &QAction::triggered, this, [&, i](bool checked) {
             resizeToMultiple(i);
         });
     }
@@ -314,7 +310,7 @@ void EmuMainWindow::createWidgets()
 
     auto fullscreen_item = new QAction(QIcon(iconset + "fullscreen.svg"), tr("&Fullscreen"));
     view_menu->addAction(fullscreen_item);
-    fullscreen_item->connect(fullscreen_item, &QAction::triggered, [&](bool checked) {
+    connect(fullscreen_item, &QAction::triggered, [&](bool checked) {
         toggleFullscreen();
     });
 
@@ -444,12 +440,12 @@ void EmuMainWindow::openFile()
     app->unpause();
 }
 
-bool EmuMainWindow::openFile(std::string filename)
+bool EmuMainWindow::openFile(const std::string &filename)
 {
     if (app->openFile(filename))
     {
         auto &ru = app->config->recently_used;
-        auto it = std::find(ru.begin(), ru.end(), filename);
+        auto it = std::ranges::find(ru, filename);
         if (it != ru.end())
             ru.erase(it);
         ru.insert(ru.begin(), filename);
diff --git a/qt/src/EmuMainWindow.hpp b/qt/src/EmuMainWindow.hpp
index 24815039..8d899a5c 100644
--- a/qt/src/EmuMainWindow.hpp
+++ b/qt/src/EmuMainWindow.hpp
@@ -33,7 +33,7 @@ class EmuMainWindow : public QMainWindow
     void pauseContinue();
     bool isActivelyDrawing();
     void openFile();
-    bool openFile(std::string filename);
+    bool openFile(const std::string &filename);
     void recreateUIAssets();
     void shaderChanged();
     void gameChanging();
diff --git a/qt/src/SoundPanel.cpp b/qt/src/SoundPanel.cpp
index 74955122..a60f946f 100644
--- a/qt/src/SoundPanel.cpp
+++ b/qt/src/SoundPanel.cpp
@@ -2,7 +2,7 @@
 #include "EmuApplication.hpp"
 #include "EmuConfig.hpp"
 
-static const int playback_rates[] = { 96000, 48000, 44100 };
+static constexpr int playback_rates[] = { 96000, 48000, 44100 };
 
 SoundPanel::SoundPanel(EmuApplication *app_)
     : app(app_)
@@ -74,9 +74,7 @@ SoundPanel::SoundPanel(EmuApplication *app_)
     });
 }
 
-SoundPanel::~SoundPanel()
-{
-}
+SoundPanel::~SoundPanel() = default;
 
 void SoundPanel::updateInputRate()
 {
diff --git a/qt/src/main.cpp b/qt/src/main.cpp
index 58d459c9..dc819f45 100644
--- a/qt/src/main.cpp
+++ b/qt/src/main.cpp
@@ -27,11 +27,11 @@ int main(int argc, char *argv[])
 
     QGuiApplication::setDesktopFileName("snes9x-gtk");
 
-    if (emu.qtapp->platformName() == "windows")
+    if (QApplication::platformName() == "windows")
     {
-        if (emu.qtapp->styleHints()->colorScheme() == Qt::ColorScheme::Dark)
+        if (QApplication::styleHints()->colorScheme() == Qt::ColorScheme::Dark)
         {
-            emu.qtapp->setStyle("fusion");
+            QApplication::setStyle("fusion");
 
             const QColor darkGray(53, 53, 53);
             const QColor gray(128, 128, 128);
@@ -59,11 +59,11 @@ int main(int argc, char *argv[])
             darkPalette.setColor(QPalette::Disabled, QPalette::WindowText, gray);
             darkPalette.setColor(QPalette::Disabled, QPalette::Text, gray);
             darkPalette.setColor(QPalette::Disabled, QPalette::Light, darkGray);
-            emu.qtapp->setPalette(darkPalette);
+            QApplication::setPalette(darkPalette);
         }
         else
         {
-            emu.qtapp->setStyle("windowsvista");
+            QApplication::setStyle("windowsvista");
         }
     }