qrenderdoc: Build with Qt6 as well as Qt5

Qt6 removed a long list of what qrenderdoc uses: QtX11Extras and QX11Info,
QRegExp, QDesktopWidget, QTextCodec, Qt::AA_X11InitThreads,
QLayout::setMargin and margin, QStyleOption::init, QPalette::foreground,
QPalette::Foreground and Background, QStyle::PE_IndicatorViewItemCheck,
QPainter::drawRoundRect and HighQualityAntialiasing, QFontMetrics::width,
QWheelEvent::delta, pos, x and orientation, QTime::start and elapsed,
QString::null and midRef, QModelIndex::child, QSet and QVector::toList,
QMetaType::registerComparators, QComboBox::setAutoCompletion,
QAbstractItemView::viewOptions, QSortFilterProxyModel::setFilterRegExp,
Qt::MidButton, Qt::ImMicroFocus, QVariant's relational operators and the
QString::SplitBehavior flags. It also made QVector an alias of QList,
turned QNetworkReply::error into a getter with errorOccurred as the
signal, made QLabel::pixmap return by value, QTimer::QPrivateSignal and
the event copy constructors inaccessible, changed QWidget::enterEvent to
take a QEnterEvent, and stopped converting 0 to any QFlags or NULL to
QPointer.

Port each of those, keeping the Qt5 spelling wherever the replacement is
newer than the Qt 5.6 this still builds against. QTextCodec is the one
exception: rather than rewrite scintilla's conversion layer, take it from
the Qt5Compat module that Qt ships for exactly this.

Qt6 also ignores a CONFIG request below c++17, so qrenderdoc.pro's
"CONFIG += c++14" left the standard up to the compiler's default. That is
gnu++20 with GCC 16, where the replay API structs that declare a
defaulted default constructor are no longer aggregates and the returns
that brace-initialise them stop compiling. Ask for c++17 with Qt6.

Finally, Qt6 gave QString an operator+=(QUtf8StringView) and an rvalue
operator+, which an rdcstr or rdcinflexiblestr converts to just as
readily as it does to QString, so appending or concatenating one became
ambiguous; exact-match operators settle it.

diff --git a/qrenderdoc/3rdparty/flowlayout/FlowLayout.cpp b/qrenderdoc/3rdparty/flowlayout/FlowLayout.cpp
index f91dc07..b48f677 100644
--- a/qrenderdoc/3rdparty/flowlayout/FlowLayout.cpp
+++ b/qrenderdoc/3rdparty/flowlayout/FlowLayout.cpp
@@ -115,7 +115,7 @@ QLayoutItem *FlowLayout::takeAt(int index)
 
 Qt::Orientations FlowLayout::expandingDirections() const
 {
-    return 0;
+    return Qt::Orientations();
 }
 
 bool FlowLayout::hasHeightForWidth() const
@@ -160,7 +160,8 @@ QSize FlowLayout::minimumSize() const
     foreach (item, itemList)
         size = size.expandedTo(item->minimumSize());
 
-    size += QSize(2*margin(), 2*margin());
+    const QMargins margins = contentsMargins();
+    size += QSize(margins.left() + margins.right(), margins.top() + margins.bottom());
 
     if(!m_prevRect.isEmpty())
     {
diff --git a/qrenderdoc/3rdparty/scintilla/include/qt/ScintillaEditBase.h b/qrenderdoc/3rdparty/scintilla/include/qt/ScintillaEditBase.h
index a7ba734..98ac773 100644
--- a/qrenderdoc/3rdparty/scintilla/include/qt/ScintillaEditBase.h
+++ b/qrenderdoc/3rdparty/scintilla/include/qt/ScintillaEditBase.h
@@ -16,6 +16,7 @@
 #include "../Scintilla.h"
 
 #include <QAbstractScrollArea>
+#include <QElapsedTimer>
 #include <QMimeData>
 #include <QTime>
 
@@ -137,9 +138,9 @@ protected:
 private:
 	ScintillaQt *sqt;
 
-	QTime time;
+  QElapsedTimer time;
 
-	int preeditPos;
+  int preeditPos;
 	QString preeditString;
 
 	int wheelDelta;
diff --git a/qrenderdoc/3rdparty/scintilla/qt/ScintillaEditBase/PlatQt.cpp b/qrenderdoc/3rdparty/scintilla/qt/ScintillaEditBase/PlatQt.cpp
index fd41e57..bca2640 100644
--- a/qrenderdoc/3rdparty/scintilla/qt/ScintillaEditBase/PlatQt.cpp
+++ b/qrenderdoc/3rdparty/scintilla/qt/ScintillaEditBase/PlatQt.cpp
@@ -12,28 +12,28 @@
 #include "Scintilla.h"
 #include "FontQuality.h"
 
+#include <QAction>
 #include <QApplication>
-#include <QFont>
 #include <QColor>
-#include <QRect>
+#include <QElapsedTimer>
+#include <QFont>
+#include <QLibrary>
+#include <QListWidget>
+#include <QMenu>
+#include <QMessageBox>
 #include <QPaintDevice>
 #include <QPaintEngine>
-#include <QWidget>
-#include <QPixmap>
 #include <QPainter>
-#include <QMenu>
-#include <QAction>
-#include <QTime>
-#include <QMessageBox>
-#include <QTextCodec>
-#include <QListWidget>
-#include <QVarLengthArray>
+#include <QPixmap>
+#include <QRect>
+#include <QScreen>
 #include <QScrollBar>
-#include <QDesktopWidget>
+#include <QTextCodec>
 #include <QTextLayout>
 #include <QTextLine>
-#include <QLibrary>
-#include <QElapsedTimer>
+#include <QTime>
+#include <QVarLengthArray>
+#include <QWidget>
 #include <cstdio>
 
 #ifdef SCI_NAMESPACE
@@ -330,7 +330,8 @@ void SurfaceImpl::RoundedRectangle(PRectangle rc,
 {
 	PenColour(fore);
 	BrushColour(back);
-	GetPainter()->drawRoundRect(QRectFFromPRect(rc));
+  const QRectF rect = QRectFFromPRect(rc);
+  GetPainter()->drawRoundedRect(rect, 25.0, 25.0, Qt::RelativeSize);
 }
 
 void SurfaceImpl::AlphaRectangle(PRectangle rc,
@@ -510,13 +511,21 @@ XYPOSITION SurfaceImpl::WidthText(Font &font, const char *s, int len)
 	QFontMetricsF metrics(*FontPointer(font), device);
 	SetCodec(font);
 	QString string = codec->toUnicode(s, len);
-	return metrics.width(string);
+#if QT_VERSION >= QT_VERSION_CHECK(5, 11, 0)
+  return metrics.horizontalAdvance(string);
+#else
+  return metrics.width(string);
+#endif
 }
 
 XYPOSITION SurfaceImpl::WidthChar(Font &font, char ch)
 {
 	QFontMetricsF metrics(*FontPointer(font), device);
-	return metrics.width(QChar::fromLatin1(ch));
+#if QT_VERSION >= QT_VERSION_CHECK(5, 11, 0)
+  return metrics.horizontalAdvance(QChar::fromLatin1(ch));
+#else
+  return metrics.width(QChar::fromLatin1(ch));
+#endif
 }
 
 XYPOSITION SurfaceImpl::Ascent(Font &font)
@@ -651,11 +660,18 @@ void Window::SetPositionRelative(PRectangle rc, Window relativeTo)
 	ox += rc.left;
 	oy += rc.top;
 
-	QDesktopWidget *desktop = QApplication::desktop();
-	QRect rectDesk = desktop->availableGeometry(QPoint(ox, oy));
-	/* do some corrections to fit into screen */
-	int sizex = rc.right - rc.left;
-	int sizey = rc.bottom - rc.top;
+#if QT_VERSION >= QT_VERSION_CHECK(5, 10, 0)
+  const QScreen *screen = QGuiApplication::screenAt(QPoint(ox, oy));
+  if(!screen)
+    screen = QGuiApplication::primaryScreen();
+  QRect rectDesk = screen->availableGeometry();
+#else
+  QDesktopWidget *desktop = QApplication::desktop();
+  QRect rectDesk = desktop->availableGeometry(QPoint(ox, oy));
+#endif
+  /* do some corrections to fit into screen */
+  int sizex = rc.right - rc.left;
+  int sizey = rc.bottom - rc.top;
 	int screenWidth = rectDesk.width();
 	if (ox < rectDesk.x())
 		ox = rectDesk.x();
@@ -738,11 +754,17 @@ PRectangle Window::GetMonitorRect(Point pt)
 {
 	QPoint originGlobal = window(wid)->mapToGlobal(QPoint(0, 0));
 	QPoint posGlobal = window(wid)->mapToGlobal(QPoint(pt.x, pt.y));
-	QDesktopWidget *desktop = QApplication::desktop();
-	QRect rectScreen = desktop->availableGeometry(posGlobal);
-	rectScreen.translate(-originGlobal.x(), -originGlobal.y());
-	return PRectangle(rectScreen.left(), rectScreen.top(),
-	        rectScreen.right(), rectScreen.bottom());
+#if QT_VERSION >= QT_VERSION_CHECK(5, 10, 0)
+  const QScreen *screen = QGuiApplication::screenAt(posGlobal);
+  if(!screen)
+    screen = QGuiApplication::primaryScreen();
+  QRect rectScreen = screen->availableGeometry();
+#else
+  QDesktopWidget *desktop = QApplication::desktop();
+  QRect rectScreen = desktop->availableGeometry(posGlobal);
+#endif
+  rectScreen.translate(-originGlobal.x(), -originGlobal.y());
+  return PRectangle(rectScreen.left(), rectScreen.top(), rectScreen.right(), rectScreen.bottom());
 }
 
 
@@ -790,7 +812,11 @@ public:
 
 protected:
 	virtual void mouseDoubleClickEvent(QMouseEvent *event);
-	virtual QStyleOptionViewItem viewOptions() const;
+#if QT_VERSION >= QT_VERSION_CHECK(6, 0, 0)
+  void initViewItemOption(QStyleOptionViewItem *option) const override;
+#else
+  virtual QStyleOptionViewItem viewOptions() const;
+#endif
 
 private:
 	CallBackAction doubleClickAction;
@@ -1089,12 +1115,20 @@ void ListWidget::mouseDoubleClickEvent(QMouseEvent * /* event */)
 	}
 }
 
+#if QT_VERSION >= QT_VERSION_CHECK(6, 0, 0)
+void ListWidget::initViewItemOption(QStyleOptionViewItem *option) const
+{
+  QListWidget::initViewItemOption(option);
+  option->state |= QStyle::State_Active;
+}
+#else
 QStyleOptionViewItem ListWidget::viewOptions() const
 {
 	QStyleOptionViewItem result = QListWidget::viewOptions();
 	result.state |= QStyle::State_Active;
 	return result;
 }
+#endif
 
 //----------------------------------------------------------------------
 
diff --git a/qrenderdoc/3rdparty/scintilla/qt/ScintillaEditBase/PlatQt.h b/qrenderdoc/3rdparty/scintilla/qt/ScintillaEditBase/PlatQt.h
index be35d81..4e1171d 100644
--- a/qrenderdoc/3rdparty/scintilla/qt/ScintillaEditBase/PlatQt.h
+++ b/qrenderdoc/3rdparty/scintilla/qt/ScintillaEditBase/PlatQt.h
@@ -17,6 +17,10 @@
 #include <QPainter>
 #include <QHash>
 
+QT_BEGIN_NAMESPACE
+class QTextCodec;
+QT_END_NAMESPACE
+
 #ifdef SCI_NAMESPACE
 namespace Scintilla {
 #endif
diff --git a/qrenderdoc/3rdparty/scintilla/qt/ScintillaEditBase/ScintillaEditBase.cpp b/qrenderdoc/3rdparty/scintilla/qt/ScintillaEditBase/ScintillaEditBase.cpp
index 77452c7..6bb0bee 100644
--- a/qrenderdoc/3rdparty/scintilla/qt/ScintillaEditBase/ScintillaEditBase.cpp
+++ b/qrenderdoc/3rdparty/scintilla/qt/ScintillaEditBase/ScintillaEditBase.cpp
@@ -152,30 +152,41 @@ void ScintillaEditBase::paintEvent(QPaintEvent *event)
 
 void ScintillaEditBase::wheelEvent(QWheelEvent *event)
 {
-	if (event->orientation() == Qt::Horizontal) {
-		if (horizontalScrollBarPolicy() == Qt::ScrollBarAlwaysOff)
-			event->ignore();
+#if QT_VERSION >= QT_VERSION_CHECK(5, 14, 0)
+  if(event->angleDelta().x() != 0 && event->angleDelta().y() == 0)
+  {
+#else
+  if(event->orientation() == Qt::Horizontal)
+  {
+#endif
+    if(horizontalScrollBarPolicy() == Qt::ScrollBarAlwaysOff)
+      event->ignore();
 		else
 			QAbstractScrollArea::wheelEvent(event);
 	} else {
 		if (QApplication::keyboardModifiers() & Qt::ControlModifier) {
 			// Zoom! We play with the font sizes in the styles.
 			// Number of steps/line is ignored, we just care if sizing up or down
-			if (event->delta() > 0) {
-				sqt->KeyCommand(SCI_ZOOMIN);
-			} else {
-				sqt->KeyCommand(SCI_ZOOMOUT);
-			}
-		} else {
-			// Ignore wheel events when the scroll bars are disabled.
-			if (verticalScrollBarPolicy() == Qt::ScrollBarAlwaysOff) {
+      if(event->angleDelta().y() > 0)
+      {
+        sqt->KeyCommand(SCI_ZOOMIN);
+      }
+      else
+      {
+        sqt->KeyCommand(SCI_ZOOMOUT);
+      }
+    }
+    else
+    {
+      // Ignore wheel events when the scroll bars are disabled.
+      if (verticalScrollBarPolicy() == Qt::ScrollBarAlwaysOff) {
 				event->ignore();
 			} else {
 				// Scroll
 				QAbstractScrollArea::wheelEvent(event);
 			}
-		}
-	}
+    }
+  }
 }
 
 void ScintillaEditBase::focusInEvent(QFocusEvent *event)
@@ -293,18 +304,18 @@ void ScintillaEditBase::mousePressEvent(QMouseEvent *event)
 
 	emit buttonPressed(event);
 
-	if (event->button() == Qt::MidButton &&
-	    QApplication::clipboard()->supportsSelection()) {
-		SelectionPosition selPos = sqt->SPositionFromLocation(
-					pos, false, false, sqt->UserVirtualSpace());
-		sqt->sel.Clear();
+  if(event->button() == Qt::MiddleButton && QApplication::clipboard()->supportsSelection())
+  {
+    SelectionPosition selPos = sqt->SPositionFromLocation(pos, false, false, sqt->UserVirtualSpace());
+    sqt->sel.Clear();
 		sqt->SetSelection(selPos, selPos);
 		sqt->PasteFromMode(QClipboard::Selection);
 		return;
-	}
+  }
 
-	if (event->button() == Qt::LeftButton) {
-		bool shift = QApplication::keyboardModifiers() & Qt::ShiftModifier;
+  if(event->button() == Qt::LeftButton)
+  {
+    bool shift = QApplication::keyboardModifiers() & Qt::ShiftModifier;
 		bool ctrl  = QApplication::keyboardModifiers() & Qt::ControlModifier;
 #ifdef Q_WS_X11
 		// On X allow choice of rectangular modifier since most window
@@ -315,9 +326,9 @@ void ScintillaEditBase::mousePressEvent(QMouseEvent *event)
 #endif
 
 		sqt->ButtonDown(pos, time.elapsed(), shift, ctrl, alt);
-	}
+  }
 
-	if (event->button() == Qt::RightButton) {
+  if (event->button() == Qt::RightButton) {
 		bool shift = QApplication::keyboardModifiers() & Qt::ShiftModifier;
 		bool ctrl  = QApplication::keyboardModifiers() & Qt::ControlModifier;
 		bool alt   = QApplication::keyboardModifiers() & Qt::AltModifier;
@@ -610,16 +621,16 @@ QVariant ScintillaEditBase::inputMethodQuery(Qt::InputMethodQuery query) const
 	int line = send(SCI_LINEFROMPOSITION, pos);
 
 	switch (query) {
-		case Qt::ImMicroFocus:
-		{
-			int startPos = (preeditPos >= 0) ? preeditPos : pos;
+    case Qt::ImCursorRectangle:
+    {
+      int startPos = (preeditPos >= 0) ? preeditPos : pos;
 			Point pt = sqt->LocationFromPosition(startPos);
 			int width = send(SCI_GETCARETWIDTH);
 			int height = send(SCI_TEXTHEIGHT, line);
 			return QRect(pt.x, pt.y, width, height);
-		}
+    }
 
-		case Qt::ImFont:
+    case Qt::ImFont:
 		{
 			char fontName[64];
 			int style = send(SCI_GETSTYLEAT, pos);
diff --git a/qrenderdoc/3rdparty/scintilla/qt/ScintillaEditBase/ScintillaEditBase.h b/qrenderdoc/3rdparty/scintilla/qt/ScintillaEditBase/ScintillaEditBase.h
index 7c52e56..ad37c40 100644
--- a/qrenderdoc/3rdparty/scintilla/qt/ScintillaEditBase/ScintillaEditBase.h
+++ b/qrenderdoc/3rdparty/scintilla/qt/ScintillaEditBase/ScintillaEditBase.h
@@ -16,6 +16,7 @@
 #include "Scintilla.h"
 
 #include <QAbstractScrollArea>
+#include <QElapsedTimer>
 #include <QMimeData>
 #include <QTime>
 
@@ -137,10 +138,10 @@ protected:
 private:
 	ScintillaQt *sqt;
 
-	QTime time;
+  QElapsedTimer time;
 
-	int preeditPos;
-	QString preeditString;
+  int preeditPos;
+  QString preeditString;
 
 	int wheelDelta;
 
diff --git a/qrenderdoc/3rdparty/toolwindowmanager/ToolWindowManager.cpp b/qrenderdoc/3rdparty/toolwindowmanager/ToolWindowManager.cpp
index 0e496b8..98a7d82 100644
--- a/qrenderdoc/3rdparty/toolwindowmanager/ToolWindowManager.cpp
+++ b/qrenderdoc/3rdparty/toolwindowmanager/ToolWindowManager.cpp
@@ -25,7 +25,6 @@
 #include "ToolWindowManager.h"
 #include <QApplication>
 #include <QDebug>
-#include <QDesktopWidget>
 #include <QDrag>
 #include <QEvent>
 #include <QMetaMethod>
@@ -70,7 +69,7 @@ ToolWindowManager::ToolWindowManager(QWidget *parent) : QWidget(parent)
   m_hoverArea = NULL;
 
   QPalette pal = palette();
-  pal.setColor(QPalette::Background, pal.color(QPalette::Highlight));
+  pal.setColor(QPalette::Window, pal.color(QPalette::Highlight));
 
   m_previewOverlay = new QWidget(NULL);
   m_previewOverlay->setAutoFillBackground(true);
@@ -664,7 +663,7 @@ void ToolWindowManager::restoreState(const QVariantMap &dataMap)
     wrapper->show();
     if(wrapper->windowState() & Qt::WindowMaximized)
     {
-      wrapper->setWindowState(0);
+      wrapper->setWindowState(Qt::WindowNoState);
       wrapper->setWindowState(Qt::WindowMaximized);
     }
   }
@@ -1350,7 +1349,6 @@ void ToolWindowManager::drawHotspotPixmaps()
     QPainter p(&m_pixmaps[ref]);
     p.setCompositionMode(QPainter::CompositionMode_Source);
     p.setRenderHint(QPainter::Antialiasing);
-    p.setRenderHint(QPainter::HighQualityAntialiasing);
 
     QRectF rect(0, 0, m_dropHotspotDimension, m_dropHotspotDimension);
 
diff --git a/qrenderdoc/3rdparty/toolwindowmanager/ToolWindowManagerArea.cpp b/qrenderdoc/3rdparty/toolwindowmanager/ToolWindowManagerArea.cpp
index db951bf..5368b38 100644
--- a/qrenderdoc/3rdparty/toolwindowmanager/ToolWindowManagerArea.cpp
+++ b/qrenderdoc/3rdparty/toolwindowmanager/ToolWindowManagerArea.cpp
@@ -194,7 +194,7 @@ bool ToolWindowManagerArea::eventFilter(QObject *object, QEvent *event)
         // stop internal tab drag in QTabBar
         QMouseEvent *releaseEvent =
             new QMouseEvent(QEvent::MouseButtonRelease, static_cast<QMouseEvent *>(event)->pos(),
-                            Qt::LeftButton, Qt::LeftButton, 0);
+                            Qt::LeftButton, Qt::LeftButton, Qt::NoModifier);
         qApp->sendEvent(tabBar(), releaseEvent);
         m_manager->startDrag(QList<QWidget *>() << toolWindow, NULL);
       }
diff --git a/qrenderdoc/3rdparty/toolwindowmanager/ToolWindowManagerTabBar.cpp b/qrenderdoc/3rdparty/toolwindowmanager/ToolWindowManagerTabBar.cpp
index 2b71ca4..c73bcc9 100644
--- a/qrenderdoc/3rdparty/toolwindowmanager/ToolWindowManagerTabBar.cpp
+++ b/qrenderdoc/3rdparty/toolwindowmanager/ToolWindowManagerTabBar.cpp
@@ -51,8 +51,8 @@ ToolWindowManagerTabBar::ToolWindowManagerTabBar(QWidget *parent) : QTabBar(pare
 
   buttonOpt.initFrom(parentWidget());
   buttonOpt.iconSize = QSize(size, size);
-  buttonOpt.subControls = 0;
-  buttonOpt.activeSubControls = 0;
+  buttonOpt.subControls = QStyle::SubControls();
+  buttonOpt.activeSubControls = QStyle::SubControls();
   buttonOpt.features = QStyleOptionToolButton::None;
   buttonOpt.arrowType = Qt::NoArrow;
   buttonOpt.state |= QStyle::State_AutoRaise;
@@ -157,8 +157,8 @@ void ToolWindowManagerTabBar::paintEvent(QPaintEvent *event)
 
     buttonOpt.initFrom(parentWidget());
     buttonOpt.iconSize = QSize(size, size);
-    buttonOpt.subControls = 0;
-    buttonOpt.activeSubControls = 0;
+    buttonOpt.subControls = QStyle::SubControls();
+    buttonOpt.activeSubControls = QStyle::SubControls();
     buttonOpt.features = QStyleOptionToolButton::None;
     buttonOpt.arrowType = Qt::NoArrow;
     buttonOpt.state = QStyle::State_Active | QStyle::State_Enabled | QStyle::State_AutoRaise;
diff --git a/qrenderdoc/3rdparty/toolwindowmanager/ToolWindowManagerWrapper.cpp b/qrenderdoc/3rdparty/toolwindowmanager/ToolWindowManagerWrapper.cpp
index c0f3c19..18c3264 100644
--- a/qrenderdoc/3rdparty/toolwindowmanager/ToolWindowManagerWrapper.cpp
+++ b/qrenderdoc/3rdparty/toolwindowmanager/ToolWindowManagerWrapper.cpp
@@ -61,7 +61,6 @@ ToolWindowManagerWrapper::ToolWindowManagerWrapper(ToolWindowManager *manager, b
 
   QVBoxLayout *mainLayout = new QVBoxLayout(this);
   mainLayout->setContentsMargins(0, 0, 0, 0);
-  mainLayout->setMargin(0);
   mainLayout->setSpacing(0);
   m_manager->m_wrappers << this;
 
@@ -361,7 +360,7 @@ void ToolWindowManagerWrapper::paintEvent(QPaintEvent *)
     QStylePainter p(this);
 
     QStyleOptionFrame frameOptions;
-    frameOptions.init(this);
+    frameOptions.initFrom(this);
     p.drawPrimitive(QStyle::PE_FrameDockWidget, frameOptions);
 
     // Title must be painted after the frame, since the areas overlap, and
@@ -382,8 +381,8 @@ void ToolWindowManagerWrapper::paintEvent(QPaintEvent *)
 
     buttonOpt.initFrom(this);
     buttonOpt.iconSize = QSize(m_closeButtonSize, m_closeButtonSize);
-    buttonOpt.subControls = 0;
-    buttonOpt.activeSubControls = 0;
+    buttonOpt.subControls = QStyle::SubControls();
+    buttonOpt.activeSubControls = QStyle::SubControls();
     buttonOpt.features = QStyleOptionToolButton::None;
     buttonOpt.arrowType = Qt::NoArrow;
     buttonOpt.state = QStyle::State_Active | QStyle::State_Enabled | QStyle::State_AutoRaise;
diff --git a/qrenderdoc/Code/CaptureContext.cpp b/qrenderdoc/Code/CaptureContext.cpp
index 2b9fb4e..bda2860 100644
--- a/qrenderdoc/Code/CaptureContext.cpp
+++ b/qrenderdoc/Code/CaptureContext.cpp
@@ -585,7 +585,7 @@ rdcstr CaptureContext::LoadExtension(rdcstr name)
   for(QAction *a : m_MainWindow->GetMenuActions())
     CleanMenu(a);
 
-  m_RegisteredMenuItems.removeAll(NULL);
+  m_RegisteredMenuItems.removeAll(nullptr);
 
   return ret;
 }
@@ -1157,9 +1157,9 @@ void CaptureContext::LoadCaptureThreaded(const QString &captureFile, const Repla
       }
 
       if(m_CurWinSystem == WindowingSystem::XCB)
-        m_XCBConnection = QX11Info::connection();
+        m_XCBConnection = RDX11Connection();
       else
-        m_X11Display = QX11Info::display();
+        m_X11Display = RDX11Display();
     }
 
 #elif defined(RENDERDOC_PLATFORM_APPLE)
diff --git a/qrenderdoc/Code/CaptureContext.h b/qrenderdoc/Code/CaptureContext.h
index ca00d45..3163fdb 100644
--- a/qrenderdoc/Code/CaptureContext.h
+++ b/qrenderdoc/Code/CaptureContext.h
@@ -34,7 +34,7 @@
 #include "ReplayManager.h"
 
 #if defined(RENDERDOC_PLATFORM_LINUX)
-#include <QX11Info>
+#include "QRDX11.h"
 #endif
 
 class MainWindow;
diff --git a/qrenderdoc/Code/Interface/PersistentConfig.cpp b/qrenderdoc/Code/Interface/PersistentConfig.cpp
index ec9a760..6c4f4bc 100644
--- a/qrenderdoc/Code/Interface/PersistentConfig.cpp
+++ b/qrenderdoc/Code/Interface/PersistentConfig.cpp
@@ -298,7 +298,7 @@ void PersistentConfig::applyValues(const QVariantMap &values)
       if(settings.contains(lit("shader.debug.searchPaths")))
       {
         QStringList searchPaths = settings[lit("shader.debug.searchPaths")].toString().split(
-            QLatin1Char(';'), QString::SkipEmptyParts);
+            QLatin1Char(';'), RDSkipEmptyParts);
 
         SDObject *debug = RENDERDOC_SetConfigSetting("DXBC.Debug.SearchDirPaths");
 
diff --git a/qrenderdoc/Code/MiniQtHelper.cpp b/qrenderdoc/Code/MiniQtHelper.cpp
index 759de47..d56d177 100644
--- a/qrenderdoc/Code/MiniQtHelper.cpp
+++ b/qrenderdoc/Code/MiniQtHelper.cpp
@@ -190,7 +190,7 @@ bool MiniQtHelper::ShowWidgetAsDialog(QWidget *widget)
 
   QVBoxLayout l;
   l.addWidget(widget);
-  l.setMargin(3);
+  l.setContentsMargins(3, 3, 3, 3);
 
   m_CurrentDialog->setLayout(&l);
 
diff --git a/qrenderdoc/Code/QRDUtils.cpp b/qrenderdoc/Code/QRDUtils.cpp
index 15cc6a1..e11e18c 100644
--- a/qrenderdoc/Code/QRDUtils.cpp
+++ b/qrenderdoc/Code/QRDUtils.cpp
@@ -1897,7 +1897,7 @@ QIcon MakeSwatchIcon(QWidget *parentWidget, QColor swatchColor)
   {
     QPainter painter(&pm);
 
-    QPen pen(parentWidget->palette().foreground(), 1.0);
+    QPen pen(parentWidget->palette().windowText(), 1.0);
     painter.setPen(pen);
     painter.drawLine(QPoint(0, 0), QPoint(h - 1, 0));
     painter.drawLine(QPoint(h - 1, 0), QPoint(h - 1, h - 1));
@@ -2555,8 +2555,8 @@ QString RDDialog::getExistingDirectory(QWidget *parent, const QString &caption,
 {
   QFileDialog fd(parent, caption, dir, QString());
   fd.setAcceptMode(QFileDialog::AcceptOpen);
-  fd.setFileMode(QFileDialog::DirectoryOnly);
-  fd.setOptions(options);
+  fd.setFileMode(QFileDialog::Directory);
+  fd.setOptions(options | QFileDialog::ShowDirsOnly);
   show(&fd);
 
   if(fd.result() == QFileDialog::Accepted)
@@ -3987,7 +3987,7 @@ QVariant StructuredDataItemModel::headerData(int section, Qt::Orientation orient
 Qt::ItemFlags StructuredDataItemModel::flags(const QModelIndex &index) const
 {
   if(!index.isValid())
-    return 0;
+    return Qt::NoItemFlags;
 
   return QAbstractItemModel::flags(index);
 }
diff --git a/qrenderdoc/Code/QRDUtils.h b/qrenderdoc/Code/QRDUtils.h
index 76675aa..409b9e7 100644
--- a/qrenderdoc/Code/QRDUtils.h
+++ b/qrenderdoc/Code/QRDUtils.h
@@ -44,6 +44,47 @@
 #define ENABLE_UNIT_TESTS 0
 #endif
 
+// Qt 5.14 moved the QString::split() behaviour flags into the Qt namespace, and
+// Qt 6 removed the QString spelling
+// Qt 6 replaced QAbstractItemView::viewOptions() with initViewItemOption(),
+// which fills an option the caller owns
+#if QT_VERSION >= QT_VERSION_CHECK(6, 0, 0)
+#define RDViewOptions(view)           \
+  ([&]() {                            \
+    QStyleOptionViewItem opt;         \
+    (view)->initViewItemOption(&opt); \
+    return opt;                       \
+  }())
+#else
+#define RDViewOptions(view) ((view)->viewOptions())
+#endif
+
+// Qt 6 removed the relational operators on QVariant in favour of compare()
+inline bool RDVariantLessThan(const QVariant &left, const QVariant &right)
+{
+#if QT_VERSION >= QT_VERSION_CHECK(6, 0, 0)
+  return QVariant::compare(left, right) == QPartialOrdering::Less;
+#else
+  return left < right;
+#endif
+}
+
+// Qt 5.15 renamed the QNetworkReply::error signal, and in Qt 6 error() is only
+// the getter
+#if QT_VERSION >= QT_VERSION_CHECK(5, 15, 0)
+#define RDNetworkReplyError &QNetworkReply::errorOccurred
+#else
+#define RDNetworkReplyError OverloadedSlot<QNetworkReply::NetworkError>::of(&QNetworkReply::error)
+#endif
+
+#if QT_VERSION >= QT_VERSION_CHECK(5, 14, 0)
+#define RDSkipEmptyParts Qt::SkipEmptyParts
+#define RDKeepEmptyParts Qt::KeepEmptyParts
+#else
+#define RDSkipEmptyParts QString::SkipEmptyParts
+#define RDKeepEmptyParts QString::KeepEmptyParts
+#endif
+
 class QHeaderView;
 
 template <typename T>
diff --git a/qrenderdoc/Code/QRDX11.h b/qrenderdoc/Code/QRDX11.h
new file mode 100644
index 0000000..4907b21
--- /dev/null
+++ b/qrenderdoc/Code/QRDX11.h
@@ -0,0 +1,74 @@
+/******************************************************************************
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2019-2025 Baldur Karlsson
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ ******************************************************************************/
+
+#pragma once
+
+// Qt6 dropped QX11Info. Its replacement is the X11 native interface, which only
+// exists when Qt itself was built with xcb support, so both of these can return
+// NULL there where QX11Info would always have answered.
+
+#include <QtGlobal>
+
+struct _XDisplay;
+typedef struct _XDisplay Display;
+struct xcb_connection_t;
+
+#if QT_VERSION >= QT_VERSION_CHECK(6, 0, 0)
+
+#include <QtGui/qguiapplication_platform.h>
+#include <QGuiApplication>
+
+inline Display *RDX11Display()
+{
+#if QT_CONFIG(xcb)
+  if(auto *x11 = qGuiApp->nativeInterface<QNativeInterface::QX11Application>())
+    return x11->display();
+#endif
+  return NULL;
+}
+
+inline xcb_connection_t *RDX11Connection()
+{
+#if QT_CONFIG(xcb)
+  if(auto *x11 = qGuiApp->nativeInterface<QNativeInterface::QX11Application>())
+    return x11->connection();
+#endif
+  return NULL;
+}
+
+#else
+
+#include <QX11Info>
+
+inline Display *RDX11Display()
+{
+  return QX11Info::display();
+}
+
+inline xcb_connection_t *RDX11Connection()
+{
+  return QX11Info::connection();
+}
+
+#endif
diff --git a/qrenderdoc/Code/qprocessinfo.cpp b/qrenderdoc/Code/qprocessinfo.cpp
index a15c162..577ca45 100644
--- a/qrenderdoc/Code/qprocessinfo.cpp
+++ b/qrenderdoc/Code/qprocessinfo.cpp
@@ -122,7 +122,7 @@ QProcessList QProcessInfo::enumerate(bool includeWindowTitles)
 
 #include <QDir>
 #include <QProcess>
-#include <QRegExp>
+#include <QRegularExpression>
 #include <QStandardPaths>
 #include <QTextStream>
 
@@ -285,24 +285,26 @@ QProcessList QProcessInfo::enumerate(bool includeWindowTitles)
       // should be three lines: Window <id> \n Position: ... \n Geometry: ...
       if(winGeometry.size() >= 3)
       {
-        QRegExp pos(QStringLiteral("Position: (-?\\d+),(-?\\d+)"));
-        QRegExp geometry(QStringLiteral("Geometry: (\\d+)x(\\d+)"));
+        QRegularExpression pos(QStringLiteral("Position: (-?\\d+),(-?\\d+)"));
+        QRegularExpression geometry(QStringLiteral("Geometry: (\\d+)x(\\d+)"));
 
         QString posString = QString::fromUtf8(winGeometry[1]);
         QString geometryString = QString::fromUtf8(winGeometry[2]);
 
         int x = 0, y = 0, w = 1000, h = 1000;
 
-        if(pos.indexIn(posString) >= 0)
+        QRegularExpressionMatch posMatch = pos.match(posString);
+        if(posMatch.hasMatch())
         {
-          x = pos.cap(1).toInt();
-          y = pos.cap(2).toInt();
+          x = posMatch.captured(1).toInt();
+          y = posMatch.captured(2).toInt();
         }
 
-        if(geometry.indexIn(geometryString) >= 0)
+        QRegularExpressionMatch geometryMatch = geometry.match(geometryString);
+        if(geometryMatch.hasMatch())
         {
-          w = geometry.cap(1).toInt();
-          h = geometry.cap(2).toInt();
+          w = geometryMatch.captured(1).toInt();
+          h = geometryMatch.captured(2).toInt();
         }
 
         // some invisible windows are placed off screen, if we detect that skip it
diff --git a/qrenderdoc/Code/qrenderdoc.cpp b/qrenderdoc/Code/qrenderdoc.cpp
index 5058566..879c8cd 100644
--- a/qrenderdoc/Code/qrenderdoc.cpp
+++ b/qrenderdoc/Code/qrenderdoc.cpp
@@ -184,7 +184,9 @@ int main(int argc, char *argv[])
 {
   // call this as the very first thing - no-op on other platforms, but on linux it means
   // XInitThreads will be called allowing driver access to xlib on multiple threads.
+#if QT_VERSION < QT_VERSION_CHECK(6, 0, 0)
   QCoreApplication::setAttribute(Qt::AA_X11InitThreads);
+#endif
 
   qInstallMessageHandler(sharedLogOutput);
 
@@ -578,7 +580,7 @@ int main(int argc, char *argv[])
     {
       GlobalEnvironment env;
 #if defined(RENDERDOC_PLATFORM_LINUX)
-      env.xlibDisplay = QX11Info::display();
+      env.xlibDisplay = RDX11Display();
       if(QGuiApplication::platformName() == lit("wayland"))
       {
         env.waylandDisplay = (wl_display *)AccessWaylandPlatformInterface("display", NULL);
diff --git a/qrenderdoc/Styles/RDStyle/RDStyle.cpp b/qrenderdoc/Styles/RDStyle/RDStyle.cpp
index d5cdc95..b36e8dd 100644
--- a/qrenderdoc/Styles/RDStyle/RDStyle.cpp
+++ b/qrenderdoc/Styles/RDStyle/RDStyle.cpp
@@ -1546,7 +1546,7 @@ void RDStyle::drawPrimitive(PrimitiveElement element, const QStyleOption *opt, Q
 
     return;
   }
-  else if(element == QStyle::PE_IndicatorViewItemCheck || element == QStyle::PE_IndicatorCheckBox)
+  else if(element == QStyle::PE_IndicatorItemViewItemCheck || element == QStyle::PE_IndicatorCheckBox)
   {
     QRect rect = opt->rect;
     int w = rect.width();
diff --git a/qrenderdoc/Styles/RDStyle/RDStyle.h b/qrenderdoc/Styles/RDStyle/RDStyle.h
index 99ee1a0..d606426 100644
--- a/qrenderdoc/Styles/RDStyle/RDStyle.h
+++ b/qrenderdoc/Styles/RDStyle/RDStyle.h
@@ -99,7 +99,7 @@ protected:
   bool eventFilter(QObject *watched, QEvent *event) override;
 
   const QBrush &outlineBrush(const QPalette &pal,
-                             QPalette::ColorRole role = QPalette::Foreground) const;
+                             QPalette::ColorRole role = QPalette::WindowText) const;
 
   void drawRoundedRectBorder(const QStyleOption *opt, QPainter *p, const QWidget *widget,
                              QPalette::ColorRole fillRole, bool shadow) const;
diff --git a/qrenderdoc/Styles/RDTweakedNativeStyle/RDTweakedNativeStyle.cpp b/qrenderdoc/Styles/RDTweakedNativeStyle/RDTweakedNativeStyle.cpp
index 3334954..b98147c 100644
--- a/qrenderdoc/Styles/RDTweakedNativeStyle/RDTweakedNativeStyle.cpp
+++ b/qrenderdoc/Styles/RDTweakedNativeStyle/RDTweakedNativeStyle.cpp
@@ -521,7 +521,11 @@ void RDTweakedNativeStyle::drawControl(ControlElement control, const QStyleOptio
       // elide text from the right if there's not enough space
       QFontMetrics metrics(toolopt->font);
 
+#if QT_VERSION >= QT_VERSION_CHECK(5, 11, 0)
+      int space = metrics.horizontalAdvance(QLatin1Char(' '));
+#else
       int space = metrics.width(QLatin1Char(' '));
+#endif
       textRect = QStyle::visualRect(opt->direction, rect, textRect);
 
       if(toolopt->toolButtonStyle == Qt::ToolButtonTextOnly)
diff --git a/qrenderdoc/Widgets/AnnotationDisplay.cpp b/qrenderdoc/Widgets/AnnotationDisplay.cpp
index e47f162..5c5cbf9 100644
--- a/qrenderdoc/Widgets/AnnotationDisplay.cpp
+++ b/qrenderdoc/Widgets/AnnotationDisplay.cpp
@@ -50,7 +50,8 @@ AnnotationDisplay::AnnotationDisplay(ICaptureContext &ctx, bool standalone, QWid
 
   QVBoxLayout *layout = new QVBoxLayout(this);
   layout->setSpacing(0);
-  layout->setMargin(m_Standalone ? 3 : 0);
+  const int margin = m_Standalone ? 3 : 0;
+  layout->setContentsMargins(margin, margin, margin, margin);
 
   layout->addWidget(m_Tree);
 
diff --git a/qrenderdoc/Widgets/Extended/RDHeaderView.cpp b/qrenderdoc/Widgets/Extended/RDHeaderView.cpp
index 517bdb5..1028c01 100644
--- a/qrenderdoc/Widgets/Extended/RDHeaderView.cpp
+++ b/qrenderdoc/Widgets/Extended/RDHeaderView.cpp
@@ -491,7 +491,11 @@ void RDHeaderView::resizeSectionsWithHints()
     }
   }
 
+#if QT_VERSION >= QT_VERSION_CHECK(6, 0, 0)
+  resizeSections(sizes);
+#else
   resizeSections(sizes.toList());
+#endif
 }
 
 void RDHeaderView::setColumnStretchHints(const QList<int> &hints)
@@ -857,7 +861,7 @@ void RDHeaderView::paintEvent(QPaintEvent *e)
   if(accumRect.right() < e->rect().right())
   {
     QStyleOption opt;
-    opt.init(this);
+    opt.initFrom(this);
     opt.state |= QStyle::State_Horizontal;
     opt.rect =
         QRect(accumRect.right() + 1, 0, e->rect().right() - accumRect.right(), viewport()->height());
diff --git a/qrenderdoc/Widgets/Extended/RDLabel.cpp b/qrenderdoc/Widgets/Extended/RDLabel.cpp
index 6694e1a..712c4f6 100644
--- a/qrenderdoc/Widgets/Extended/RDLabel.cpp
+++ b/qrenderdoc/Widgets/Extended/RDLabel.cpp
@@ -163,7 +163,12 @@ void RDLabel::leaveEvent(QEvent *event)
 
 void RDLabel::resizeEvent(QResizeEvent *event)
 {
+#if QT_VERSION >= QT_VERSION_CHECK(6, 0, 0)
+  const QPixmap pm = pixmap();
+  const QPixmap *p = pm.isNull() ? NULL : &pm;
+#else
   const QPixmap *p = pixmap();
+#endif
   if(m_preserveRatio && p)
   {
     QRect r = rect();
diff --git a/qrenderdoc/Widgets/Extended/RDTableView.h b/qrenderdoc/Widgets/Extended/RDTableView.h
index f251cb7..0ef9b00 100644
--- a/qrenderdoc/Widgets/Extended/RDTableView.h
+++ b/qrenderdoc/Widgets/Extended/RDTableView.h
@@ -65,7 +65,20 @@ public:
 
   void setColumnGroupRole(int role);
   int columnGroupRole() const { return m_columnGroupRole; }
+#if QT_VERSION >= QT_VERSION_CHECK(6, 0, 0)
+  void initViewItemOption(QStyleOptionViewItem *option) const override
+  {
+    QTableView::initViewItemOption(option);
+  }
+  QStyleOptionViewItem viewOptions() const
+  {
+    QStyleOptionViewItem opt;
+    initViewItemOption(&opt);
+    return opt;
+  }
+#else
   QStyleOptionViewItem viewOptions() const override { return QTableView::viewOptions(); }
+#endif
   void setPinnedColumns(int numColumns);
   int pinnedColumns() const { return m_pinnedColumns; }
 protected:
diff --git a/qrenderdoc/Widgets/Extended/RDToolTip.cpp b/qrenderdoc/Widgets/Extended/RDToolTip.cpp
index 6b8b1b9..db310c2 100644
--- a/qrenderdoc/Widgets/Extended/RDToolTip.cpp
+++ b/qrenderdoc/Widgets/Extended/RDToolTip.cpp
@@ -24,9 +24,9 @@
 
 #include "RDToolTip.h"
 #include <QApplication>
-#include <QDesktopWidget>
 #include <QMouseEvent>
 #include <QProxyStyle>
+#include <QScreen>
 #include <QStyleOptionFrame>
 #include <QStylePainter>
 
@@ -36,7 +36,13 @@ void ICustomToolTipDisplay::showTip(QWidget *widget, QString text, QModelIndex i
 
   // estimate, as this is not easily queryable
   const QPoint cursorSize(16, 16);
+#if QT_VERSION >= QT_VERSION_CHECK(5, 10, 0)
+  const QScreen *screen = QGuiApplication::screenAt(p);
+  const QRect screenAvailGeom =
+      screen ? screen->availableGeometry() : QGuiApplication::primaryScreen()->availableGeometry();
+#else
   const QRect screenAvailGeom = QApplication::desktop()->availableGeometry(p);
+#endif
 
   // start with the tooltip placed bottom-right of the cursor, as the default
   QRect tooltipRect;
@@ -94,7 +100,7 @@ void RDToolTip::paintEvent(QPaintEvent *ev)
 {
   QStylePainter p(this);
   QStyleOptionFrame opt;
-  opt.init(this);
+  opt.initFrom(this);
   p.drawPrimitive(QStyle::PE_PanelTipLabel, opt);
   p.end();
 
@@ -131,7 +137,7 @@ void RDToolTip::resizeEvent(QResizeEvent *e)
 {
   QStyleHintReturnMask frameMask;
   QStyleOption option;
-  option.init(this);
+  option.initFrom(this);
   if(style()->styleHint(QStyle::SH_ToolTip_Mask, &option, this, &frameMask))
     setMask(frameMask.region);
 
diff --git a/qrenderdoc/Widgets/Extended/RDTreeView.cpp b/qrenderdoc/Widgets/Extended/RDTreeView.cpp
index 34dea8d..d60ba6d 100644
--- a/qrenderdoc/Widgets/Extended/RDTreeView.cpp
+++ b/qrenderdoc/Widgets/Extended/RDTreeView.cpp
@@ -187,7 +187,11 @@ void RDTreeView::mouseMoveEvent(QMouseEvent *e)
 void RDTreeView::wheelEvent(QWheelEvent *e)
 {
   QTreeView::wheelEvent(e);
+#if QT_VERSION >= QT_VERSION_CHECK(5, 14, 0)
+  m_currentHoverIndex = indexAt(e->position().toPoint());
+#else
   m_currentHoverIndex = indexAt(e->pos());
+#endif
 }
 
 void RDTreeView::leaveEvent(QEvent *e)
@@ -578,8 +582,8 @@ void RDTreeView::drawRow(QPainter *painter, const QStyleOptionViewItem &options,
   {
     QPen p = painter->pen();
 
-    QColor back = options.palette.color(QPalette::Active, QPalette::Background);
-    QColor fore = options.palette.color(QPalette::Active, QPalette::Foreground);
+    QColor back = options.palette.color(QPalette::Active, QPalette::Window);
+    QColor fore = options.palette.color(QPalette::Active, QPalette::WindowText);
 
     // draw the grid lines with a colour half way between background and foreground
     painter->setPen(QPen(QColor::fromRgbF(back.redF() * 0.8 + fore.redF() * 0.2,
@@ -678,7 +682,7 @@ void RDTreeView::drawBranches(QPainter *painter, const QRect &rect, const QModel
   if(foreColVar.isValid())
   {
     foreCol = foreColVar.value<QBrush>().color();
-    opt.palette.setColor(QPalette::Foreground, foreCol);
+    opt.palette.setColor(QPalette::WindowText, foreCol);
     opt.palette.setColor(QPalette::Text, foreCol);
   }
 
@@ -707,7 +711,7 @@ void RDTreeView::drawBranches(QPainter *painter, const QRect &rect, const QModel
     if(model()->rowCount(index) == 0)
       return;
 
-    QStyleOptionViewItem branchopt = viewOptions();
+    QStyleOptionViewItem branchopt = RDViewOptions(this);
 
     branchopt.rect = primitive;
 
diff --git a/qrenderdoc/Widgets/Extended/RDTreeWidget.cpp b/qrenderdoc/Widgets/Extended/RDTreeWidget.cpp
index 1c98bb5..1aa8028 100644
--- a/qrenderdoc/Widgets/Extended/RDTreeWidget.cpp
+++ b/qrenderdoc/Widgets/Extended/RDTreeWidget.cpp
@@ -153,7 +153,7 @@ public:
   Qt::ItemFlags flags(const QModelIndex &index) const override
   {
     if(!index.isValid())
-      return 0;
+      return Qt::NoItemFlags;
 
     RDTreeWidgetItem *item = itemForIndex(index);
 
@@ -654,7 +654,7 @@ void RDTreeWidget::beginUpdate()
   m_queueUpdates = true;
 
   m_queuedItem = NULL;
-  m_lowestIndex = m_highestIndex = qMakePair<int, int>(-1, -1);
+  m_lowestIndex = m_highestIndex = qMakePair(-1, -1);
   m_queuedChildren = false;
   m_queuedRoles = 0;
 
@@ -913,8 +913,8 @@ void RDTreeWidget::itemDataChanged(RDTreeWidgetItem *item, int column, int role)
     if(m_lowestIndex.first == -1)
     {
       m_queuedItem = item;
-      m_lowestIndex = qMakePair<int, int>(row, 0);
-      m_highestIndex = qMakePair<int, int>(m_lowestIndex.first, m_headers.count() - 1);
+      m_lowestIndex = qMakePair(row, 0);
+      m_highestIndex = qMakePair(m_lowestIndex.first, m_headers.count() - 1);
     }
     else
     {
@@ -952,8 +952,8 @@ void RDTreeWidget::beginInsertChild(RDTreeWidgetItem *item, int index)
       // in a later row, but we're generally only changing data *or* adding children, not both,
       // and in either case this is primarily about batching updates not providing a minimal update
       // set
-      m_lowestIndex = qMakePair<int, int>(0, 0);
-      m_highestIndex = qMakePair<int, int>(0, m_headers.count() - 1);
+      m_lowestIndex = qMakePair(0, 0);
+      m_highestIndex = qMakePair(0, m_headers.count() - 1);
     }
     else
     {
diff --git a/qrenderdoc/Widgets/FindReplace.cpp b/qrenderdoc/Widgets/FindReplace.cpp
index 3302bbd..8534e58 100644
--- a/qrenderdoc/Widgets/FindReplace.cpp
+++ b/qrenderdoc/Widgets/FindReplace.cpp
@@ -47,8 +47,13 @@ FindReplace::FindReplace(QList<ScintillaEdit *> &scintillas, QWidget *parent)
   RDLineEdit *edit = new RDLineEdit(this);
   ui->findText->setLineEdit(edit);
 
+#if QT_VERSION >= QT_VERSION_CHECK(6, 0, 0)
+  ui->findText->setCompleter(NULL);
+  ui->replaceText->setCompleter(NULL);
+#else
   ui->findText->setAutoCompletion(false);
   ui->replaceText->setAutoCompletion(false);
+#endif
 
   QObject::connect(edit, &RDLineEdit::keyPress, [this](QKeyEvent *event) {
     if(event->key() == Qt::Key_Return || event->key() == Qt::Key_Enter)
diff --git a/qrenderdoc/Widgets/MarkerBreadcrumbs.cpp b/qrenderdoc/Widgets/MarkerBreadcrumbs.cpp
index f3b6e12..c664de7 100644
--- a/qrenderdoc/Widgets/MarkerBreadcrumbs.cpp
+++ b/qrenderdoc/Widgets/MarkerBreadcrumbs.cpp
@@ -61,7 +61,7 @@ int BreadcrumbsLayout::count() const
 
 Qt::Orientations BreadcrumbsLayout::expandingDirections() const
 {
-  return 0;
+  return Qt::Orientations();
 }
 
 QSize BreadcrumbsLayout::minimumSize() const
@@ -217,7 +217,7 @@ MarkerBreadcrumbs::MarkerBreadcrumbs(ICaptureContext &ctx, IEventBrowser *browse
 
   m_Layout = new BreadcrumbsLayout(this, m_ElidedItems);
   m_Layout->setContentsMargins(QMargins(0, 2, 0, 2));
-  m_Layout->setMargin(0);
+  m_Layout->setContentsMargins(0, 0, 0, 0);
   setLayout(m_Layout);
 
   m_ElidedMenu = new QMenu(this);
diff --git a/qrenderdoc/Widgets/ResourcePreview.cpp b/qrenderdoc/Widgets/ResourcePreview.cpp
index f679a46..6b55249 100644
--- a/qrenderdoc/Widgets/ResourcePreview.cpp
+++ b/qrenderdoc/Widgets/ResourcePreview.cpp
@@ -58,8 +58,8 @@ ResourcePreview::ResourcePreview(bool, QWidget *parent)
 
 void ResourcePreview::Initialise()
 {
-  setBackgroundRole(QPalette::Background);
-  setForegroundRole(QPalette::Foreground);
+  setBackgroundRole(QPalette::Window);
+  setForegroundRole(QPalette::WindowText);
 
   QPalette Pal(palette());
 
@@ -71,13 +71,13 @@ void ResourcePreview::Initialise()
 
   ui->slotLabel->setPalette(palette());
   ui->slotLabel->setBackgroundRole(QPalette::Dark);
-  ui->slotLabel->setForegroundRole(QPalette::Foreground);
+  ui->slotLabel->setForegroundRole(QPalette::WindowText);
   ui->slotLabel->setAutoFillBackground(true);
   ui->slotLabel->setFont(Formatter::PreferredFont());
   ui->descriptionLabel->setPalette(palette());
   ui->descriptionLabel->setAutoFillBackground(true);
   ui->descriptionLabel->setBackgroundRole(QPalette::Dark);
-  ui->descriptionLabel->setForegroundRole(QPalette::Foreground);
+  ui->descriptionLabel->setForegroundRole(QPalette::WindowText);
   ui->descriptionLabel->setFont(Formatter::PreferredFont());
 
   if(ui->thumbnail)
@@ -138,7 +138,7 @@ void ResourcePreview::setSelected(bool sel)
 {
   m_Selected = sel;
 
-  setForegroundRole(sel ? QPalette::Highlight : QPalette::Foreground);
+  setForegroundRole(sel ? QPalette::Highlight : QPalette::WindowText);
 }
 
 WindowingData ResourcePreview::GetWidgetWindowingData()
diff --git a/qrenderdoc/Widgets/TextureGoto.cpp b/qrenderdoc/Widgets/TextureGoto.cpp
index d38b968..730e821 100644
--- a/qrenderdoc/Widgets/TextureGoto.cpp
+++ b/qrenderdoc/Widgets/TextureGoto.cpp
@@ -39,7 +39,7 @@ TextureGoto::TextureGoto(QWidget *parent, std::function<void(QPoint)> callback)
 
   QHBoxLayout *hbox = new QHBoxLayout(this);
   hbox->setSpacing(5);
-  hbox->setMargin(0);
+  hbox->setContentsMargins(0, 0, 0, 0);
 
   QFrame *frame = new QFrame(this);
   frame->setGeometry(geometry());
diff --git a/qrenderdoc/Windows/BufferViewer.cpp b/qrenderdoc/Windows/BufferViewer.cpp
index cb03780..6c67283 100644
--- a/qrenderdoc/Windows/BufferViewer.cpp
+++ b/qrenderdoc/Windows/BufferViewer.cpp
@@ -296,7 +296,7 @@ public:
   {
     CameraWrapper::MouseWheel(e);
 
-    float mod = (1.0f - e->delta() / 2500.0f);
+    float mod = (1.0f - e->angleDelta().y() / 2500.0f);
 
     SetDistance(qMax(1e-6f, m_Distance * mod));
   }
@@ -497,7 +497,11 @@ struct BufferData
 {
   BufferData()
   {
+#if QT_VERSION >= QT_VERSION_CHECK(5, 14, 0)
+    refcount.storeRelaxed(1);
+#else
     refcount.store(1);
+#endif
     stride = 0;
   }
 
@@ -959,7 +963,7 @@ public:
   Qt::ItemFlags flags(const QModelIndex &index) const override
   {
     if(!index.isValid())
-      return 0;
+      return Qt::NoItemFlags;
 
     return QAbstractItemModel::flags(index);
   }
diff --git a/qrenderdoc/Windows/DebugMessageView.cpp b/qrenderdoc/Windows/DebugMessageView.cpp
index b010362..f50f5a3 100644
--- a/qrenderdoc/Windows/DebugMessageView.cpp
+++ b/qrenderdoc/Windows/DebugMessageView.cpp
@@ -63,7 +63,7 @@ public:
   Qt::ItemFlags flags(const QModelIndex &index) const override
   {
     if(!index.isValid())
-      return 0;
+      return Qt::NoItemFlags;
 
     return QAbstractItemModel::flags(index);
   }
@@ -198,7 +198,8 @@ protected:
 
   bool lessThan(const QModelIndex &left, const QModelIndex &right) const override
   {
-    return sourceModel()->data(left, SortDataRole) < sourceModel()->data(right, SortDataRole);
+    return RDVariantLessThan(sourceModel()->data(left, SortDataRole),
+                             sourceModel()->data(right, SortDataRole));
   }
 
 private:
diff --git a/qrenderdoc/Windows/DescriptorViewer.cpp b/qrenderdoc/Windows/DescriptorViewer.cpp
index f1f0f2e..29caa13 100644
--- a/qrenderdoc/Windows/DescriptorViewer.cpp
+++ b/qrenderdoc/Windows/DescriptorViewer.cpp
@@ -434,7 +434,7 @@ public:
   Qt::ItemFlags flags(const QModelIndex &index) const override
   {
     if(!index.isValid())
-      return 0;
+      return Qt::NoItemFlags;
 
     return QAbstractItemModel::flags(index);
   }
@@ -1289,7 +1289,9 @@ DescriptorViewer::DescriptorViewer(ICaptureContext &ctx, QWidget *parent)
     if(!registered)
     {
       registered = true;
+#if QT_VERSION < QT_VERSION_CHECK(6, 0, 0)
       QMetaType::registerComparators<ButtonTag>();
+#endif
     }
   }
 
diff --git a/qrenderdoc/Windows/Dialogs/CameraControlsDialog.cpp b/qrenderdoc/Windows/Dialogs/CameraControlsDialog.cpp
index 0aebd8d..f179f3d 100644
--- a/qrenderdoc/Windows/Dialogs/CameraControlsDialog.cpp
+++ b/qrenderdoc/Windows/Dialogs/CameraControlsDialog.cpp
@@ -464,7 +464,7 @@ void FetchDefaultPrimaryKeys()
 #elif defined(Q_OS_LINUX)
 
 #include <dlfcn.h>
-#include <QX11Info>
+#include "Code/QRDX11.h"
 
 // predeclare enough of xkbcommon, so we don't have a new build time dependency on it. Qt will load it for us
 extern "C" {
@@ -550,7 +550,7 @@ void FetchDefaultPrimaryKeys()
   // if both general and xcb symbols loaded, we're good to go
   if(dyn_xkb_context_new && dyn_xkb_x11_keymap_new_from_device)
   {
-    xcb_connection_t *connection = QX11Info::connection();
+    xcb_connection_t *connection = RDX11Connection();
     xkb_context *context = dyn_xkb_context_new(XKB_CONTEXT_NO_DEFAULT_INCLUDES);
     int core_device_id = dyn_xkb_x11_get_core_keyboard_device_id(connection);
     xkb_keymap *keymap = dyn_xkb_x11_keymap_new_from_device(context, connection, core_device_id,
diff --git a/qrenderdoc/Windows/Dialogs/CaptureDialog.cpp b/qrenderdoc/Windows/Dialogs/CaptureDialog.cpp
index 337a52b..16fa6fd 100644
--- a/qrenderdoc/Windows/Dialogs/CaptureDialog.cpp
+++ b/qrenderdoc/Windows/Dialogs/CaptureDialog.cpp
@@ -69,7 +69,7 @@ void CaptureDialog::initWarning(RDLabel *warning)
 
     QColor base = pal.color(QPalette::ToolTipBase);
 
-    pal.setColor(QPalette::Foreground, pal.color(QPalette::ToolTipText));
+    pal.setColor(QPalette::WindowText, pal.color(QPalette::ToolTipText));
     pal.setColor(QPalette::Window, base);
     pal.setColor(QPalette::Base, base.darker(120));
 
@@ -79,7 +79,7 @@ void CaptureDialog::initWarning(RDLabel *warning)
   calcPaletteFromStyle(NULL);
 
   warning->setBackgroundRole(QPalette::Window);
-  warning->setForegroundRole(QPalette::Foreground);
+  warning->setForegroundRole(QPalette::WindowText);
 
   QObject::connect(warning, &RDLabel::mouseMoved,
                    [warning](QMouseEvent *) { warning->setBackgroundRole(QPalette::Base); });
diff --git a/qrenderdoc/Windows/Dialogs/ConfigEditor.cpp b/qrenderdoc/Windows/Dialogs/ConfigEditor.cpp
index a024152..1607145 100644
--- a/qrenderdoc/Windows/Dialogs/ConfigEditor.cpp
+++ b/qrenderdoc/Windows/Dialogs/ConfigEditor.cpp
@@ -135,7 +135,7 @@ public:
   Qt::ItemFlags flags(const QModelIndex &index) const override
   {
     if(!index.isValid())
-      return 0;
+      return Qt::NoItemFlags;
 
     Qt::ItemFlags ret = QAbstractItemModel::flags(index);
 
@@ -251,7 +251,7 @@ public:
       }
       else if(role == Qt::TextAlignmentRole && col == Column_ResetButton)
       {
-        return Qt::AlignHCenter + Qt::AlignTop;
+        return int(Qt::AlignHCenter | Qt::AlignTop);
       }
       else if(role == Qt::ToolTipRole)
       {
@@ -419,8 +419,8 @@ void SettingDelegate::paint(QPainter *painter, const QStyleOptionViewItem &optio
       int size = m_Editor->style()->pixelMetric(QStyle::PM_SmallIconSize, 0, m_Editor);
 
       buttonOpt.iconSize = QSize(size, size);
-      buttonOpt.subControls = 0;
-      buttonOpt.activeSubControls = 0;
+      buttonOpt.subControls = QStyle::SubControls();
+      buttonOpt.activeSubControls = QStyle::SubControls();
       buttonOpt.features = QStyleOptionToolButton::None;
       buttonOpt.arrowType = Qt::NoArrow;
       buttonOpt.state = QStyle::State_Active | QStyle::State_Enabled | QStyle::State_AutoRaise;
diff --git a/qrenderdoc/Windows/Dialogs/CrashDialog.cpp b/qrenderdoc/Windows/Dialogs/CrashDialog.cpp
index e94bbf4..a6ace57 100644
--- a/qrenderdoc/Windows/Dialogs/CrashDialog.cpp
+++ b/qrenderdoc/Windows/Dialogs/CrashDialog.cpp
@@ -25,7 +25,6 @@
 #include "CrashDialog.h"
 #include <QApplication>
 #include <QDateTime>
-#include <QDesktopWidget>
 #include <QElapsedTimer>
 #include <QFileInfo>
 #include <QHttpMultiPart>
@@ -485,8 +484,7 @@ void CrashDialog::sendReport()
   multiPart->setParent(m_Request);
 
   QObject::connect(
-      m_Request, OverloadedSlot<QNetworkReply::NetworkError>::of(&QNetworkReply::error),
-      [this](QNetworkReply::NetworkError err) {
+      m_Request, RDNetworkReplyError, [this](QNetworkReply::NetworkError err) {
         ui->progressBar->setValue(0);
         if(m_Request->error() == QNetworkReply::ProtocolInvalidOperationError)
         {
diff --git a/qrenderdoc/Windows/Dialogs/PerformanceCounterSelection.cpp b/qrenderdoc/Windows/Dialogs/PerformanceCounterSelection.cpp
index 910f450..3e3c5c2 100644
--- a/qrenderdoc/Windows/Dialogs/PerformanceCounterSelection.cpp
+++ b/qrenderdoc/Windows/Dialogs/PerformanceCounterSelection.cpp
@@ -452,7 +452,7 @@ void PerformanceCounterSelection::Load()
         selectedCounters.insert(m_UuidToCounter[uuid]);
       }
 
-      SetSelectedCounters(selectedCounters.toList());
+      SetSelectedCounters(selectedCounters.values());
     }
     else
     {
diff --git a/qrenderdoc/Windows/Dialogs/UpdateDialog.cpp b/qrenderdoc/Windows/Dialogs/UpdateDialog.cpp
index be71824..2bca3ce 100644
--- a/qrenderdoc/Windows/Dialogs/UpdateDialog.cpp
+++ b/qrenderdoc/Windows/Dialogs/UpdateDialog.cpp
@@ -49,7 +49,7 @@ UpdateDialog::UpdateDialog(QString updateResponse, QWidget *parent)
   setWindowFlags((windowFlags() | Qt::MSWindowsFixedSizeDialogHint) &
                  ~Qt::WindowContextHelpButtonHint);
 
-  QStringList lines = updateResponse.split(QLatin1Char('\n'), QString::SkipEmptyParts);
+  QStringList lines = updateResponse.split(QLatin1Char('\n'), RDSkipEmptyParts);
 
   m_NewVer = lines[0];
   m_URL = lines[1];
@@ -198,16 +198,14 @@ void UpdateDialog::on_update_clicked()
                              tr("Downloading update..."));
     });
 
-    QObject::connect(
-        m_Request, OverloadedSlot<QNetworkReply::NetworkError>::of(&QNetworkReply::error),
-        [this](QNetworkReply::NetworkError err) {
-          ui->progressBar->setValue(0);
-          ui->progressText->setText(tr("Network error:\n%1").arg(m_Request->errorString()));
-          ui->update->setEnabled(true);
-          ui->close->setEnabled(true);
-          ui->close->setText(tr("Close"));
-          ui->update->setText(tr("Retry Update"));
-        });
+    QObject::connect(m_Request, RDNetworkReplyError, [this](QNetworkReply::NetworkError err) {
+      ui->progressBar->setValue(0);
+      ui->progressText->setText(tr("Network error:\n%1").arg(m_Request->errorString()));
+      ui->update->setEnabled(true);
+      ui->close->setEnabled(true);
+      ui->close->setText(tr("Close"));
+      ui->update->setText(tr("Retry Update"));
+    });
 
     QObject::connect(m_Request, &QNetworkReply::finished, [this]() {
       // if we cancelled, close the dialog now
diff --git a/qrenderdoc/Windows/Dialogs/VirtualFileDialog.cpp b/qrenderdoc/Windows/Dialogs/VirtualFileDialog.cpp
index 05db854..b423f7b 100644
--- a/qrenderdoc/Windows/Dialogs/VirtualFileDialog.cpp
+++ b/qrenderdoc/Windows/Dialogs/VirtualFileDialog.cpp
@@ -27,7 +27,7 @@
 #include <QKeyEvent>
 #include <QPainter>
 #include <QPushButton>
-#include <QRegExp>
+#include <QRegularExpression>
 #include <QSortFilterProxyModel>
 #include "Code/ReplayManager.h"
 #include "Code/Resources.h"
@@ -794,8 +794,13 @@ void VirtualFileDialog::on_filename_keyPress(QKeyEvent *e)
 
   QString text = ui->filename->text();
 
+#if QT_VERSION >= QT_VERSION_CHECK(5, 12, 0)
+  QRegularExpression re(
+      QRegularExpression::anchoredPattern(QRegularExpression::wildcardToRegularExpression(text)));
+#else
   QRegExp re(text);
   re.setPatternSyntax(QRegExp::Wildcard);
+#endif
 
   int fileCount = m_FileProxy->rowCount(curDir);
   int matches = 0, dirmatches = 0;
@@ -809,7 +814,11 @@ void VirtualFileDialog::on_filename_keyPress(QKeyEvent *e)
 
     QString filename = m_FileProxy->data(file, RemoteFileModel::FileNameRole).toString();
 
+#if QT_VERSION >= QT_VERSION_CHECK(5, 12, 0)
+    if(re.match(filename).hasMatch())
+#else
     if(re.exactMatch(filename))
+#endif
     {
       idx = file;
       dirmatches += isDir ? 1 : 0;
@@ -846,7 +855,11 @@ void VirtualFileDialog::on_filename_keyPress(QKeyEvent *e)
     fileNotFound(text);
   }
 
+#if QT_VERSION >= QT_VERSION_CHECK(5, 12, 0)
+  m_FileProxy->setFilterRegularExpression(re);
+#else
   m_FileProxy->setFilterRegExp(re);
+#endif
   m_FileProxy->refresh();
 }
 
@@ -867,7 +880,7 @@ void VirtualFileDialog::on_buttonBox_accepted()
   }
 
   // simulate enter being pressed
-  QKeyEvent fakeEvent(QEvent::KeyPress, Qt::Key_Return, 0);
+  QKeyEvent fakeEvent(QEvent::KeyPress, Qt::Key_Return, Qt::NoModifier);
   on_filename_keyPress(&fakeEvent);
 }
 
diff --git a/qrenderdoc/Windows/EventBrowser.cpp b/qrenderdoc/Windows/EventBrowser.cpp
index fd2dee4..ad23526 100644
--- a/qrenderdoc/Windows/EventBrowser.cpp
+++ b/qrenderdoc/Windows/EventBrowser.cpp
@@ -1645,7 +1645,11 @@ protected:
     int off = name.indexOf(QLatin1Char('<'));
     while(off >= 0 && off + 4 < name.size())
     {
+#if QT_VERSION >= QT_VERSION_CHECK(5, 10, 0)
+      if(name[off + 1] == QLatin1Char('/') || QStringView(name).mid(off, 5) == lit("<span"))
+#else
       if(name[off + 1] == QLatin1Char('/') || name.midRef(off, 5) == lit("<span"))
+#endif
       {
         int end = name.indexOf(QLatin1Char('>'), off);
         name.remove(off, end - off + 1);
@@ -2672,7 +2676,7 @@ and these can be queried with a filter such as <code>$action(flags & Clear|Clear
       // split by whitespace)
       QStringList flagStrings;
       for(int i = 2; i < tokens.count(); i++)
-        flagStrings.append(tokens[i].text.split(QLatin1Char('|'), QString::KeepEmptyParts));
+        flagStrings.append(tokens[i].text.split(QLatin1Char('|'), RDKeepEmptyParts));
 
       // if we have an empty string in the list somewhere that means the | list was broken
       if(flagStrings.contains(QString()))
@@ -3744,7 +3748,7 @@ void ParseErrorTipLabel::paintEvent(QPaintEvent *ev)
 {
   QStylePainter p(this);
   QStyleOptionFrame opt;
-  opt.init(this);
+  opt.initFrom(this);
   p.drawPrimitive(QStyle::PE_PanelTipLabel, opt);
   p.end();
 
@@ -3758,7 +3762,7 @@ void ParseErrorTipLabel::resizeEvent(QResizeEvent *e)
 {
   QStyleHintReturnMask frameMask;
   QStyleOption option;
-  option.init(this);
+  option.initFrom(this);
   if(style()->styleHint(QStyle::SH_ToolTip_Mask, &option, this, &frameMask))
     setMask(frameMask.region);
 
@@ -3849,7 +3853,7 @@ EventBrowser::EventBrowser(ICaptureContext &ctx, QWidget *parent)
   {
     QHBoxLayout *box = new QHBoxLayout(ui->breadcrumbStrip);
     box->setContentsMargins(QMargins(0, 0, 0, 0));
-    box->setMargin(0);
+    box->setContentsMargins(0, 0, 0, 0);
     box->setSpacing(0);
     m_Breadcrumbs = new MarkerBreadcrumbs(m_Ctx, this, this);
     box->addWidget(m_Breadcrumbs);
@@ -4729,7 +4733,7 @@ For searching arbitrary parameters consider using the <code>$param()</code> func
     {
       // stop the timer, we'll manually fire it instantly
       m_FilterSettings.Timeout->stop();
-      m_FilterSettings.Timeout->timeout({});
+      QMetaObject::invokeMethod(m_FilterSettings.Timeout, "timeout");
     }
 
     if(e->key() == Qt::Key_Down)
@@ -5490,7 +5494,7 @@ void EventBrowser::GetMaxNameLength(int &maxNameLength, int indent, bool firstch
 
   for(int i = 0, rowCount = idx.model()->rowCount(idx); i < rowCount; i++)
   {
-    GetMaxNameLength(maxNameLength, indent + 1, firstchild, idx.child(i, COL_NAME));
+    GetMaxNameLength(maxNameLength, indent + 1, firstchild, idx.model()->index(i, COL_NAME, idx));
     firstchild = false;
   }
 }
@@ -5528,7 +5532,7 @@ void EventBrowser::ExportAction(QTextStream &writer, int maxNameLength, int inde
 
   for(int i = 0, rowCount = idx.model()->rowCount(idx); i < rowCount; i++)
   {
-    ExportAction(writer, maxNameLength, indent + 1, firstchild, idx.child(i, COL_NAME));
+    ExportAction(writer, maxNameLength, indent + 1, firstchild, idx.model()->index(i, COL_NAME, idx));
     firstchild = false;
   }
 }
diff --git a/qrenderdoc/Windows/LogView.cpp b/qrenderdoc/Windows/LogView.cpp
index c77b10b..1067084 100644
--- a/qrenderdoc/Windows/LogView.cpp
+++ b/qrenderdoc/Windows/LogView.cpp
@@ -74,7 +74,7 @@ public:
   Qt::ItemFlags flags(const QModelIndex &index) const override
   {
     if(!index.isValid())
-      return 0;
+      return Qt::NoItemFlags;
 
     return QAbstractItemModel::flags(index);
   }
diff --git a/qrenderdoc/Windows/MainWindow.cpp b/qrenderdoc/Windows/MainWindow.cpp
index 2bad07c..c9e2dc2 100644
--- a/qrenderdoc/Windows/MainWindow.cpp
+++ b/qrenderdoc/Windows/MainWindow.cpp
@@ -35,6 +35,7 @@
 #include <QProgressBar>
 #include <QProgressDialog>
 #include <QShortcut>
+#include <QStandardPaths>
 #include <QToolButton>
 #include <QToolTip>
 #include "Code/QRDUtils.h"
@@ -82,10 +83,9 @@ void NetworkWorker::get(QUrl url)
 
   // connect up error and finished slots on *this* thread, and in the lambda emit signals to
   // cross-thread back onto the UI thread.
-  QObject::connect(req, OverloadedSlot<QNetworkReply::NetworkError>::of(&QNetworkReply::error),
-                   [this, req](QNetworkReply::NetworkError) {
-                     emit requestFailed(req->url(), req->errorString());
-                   });
+  QObject::connect(req, RDNetworkReplyError, [this, req](QNetworkReply::NetworkError) {
+    emit requestFailed(req->url(), req->errorString());
+  });
 
   QObject::connect(req, &QNetworkReply::finished, [this, req]() {
     if(req->error() != QNetworkReply::NoError)
@@ -658,7 +658,7 @@ void MainWindow::on_action_Open_Capture_with_Options_triggered()
 
   QVBoxLayout l;
   l.addWidget(replayOptions);
-  l.setMargin(3);
+  l.setContentsMargins(3, 3, 3, 3);
   l.setSizeConstraint(QLayout::SetFixedSize);
 
   openWithOptions->setLayout(&l);
diff --git a/qrenderdoc/Windows/PerformanceCounterViewer.cpp b/qrenderdoc/Windows/PerformanceCounterViewer.cpp
index 138e1b4..e6e1b52 100644
--- a/qrenderdoc/Windows/PerformanceCounterViewer.cpp
+++ b/qrenderdoc/Windows/PerformanceCounterViewer.cpp
@@ -122,7 +122,7 @@ public:
   Qt::ItemFlags flags(const QModelIndex &index) const override
   {
     if(!index.isValid())
-      return 0;
+      return Qt::NoItemFlags;
 
     return QAbstractItemModel::flags(index);
   }
@@ -136,7 +136,7 @@ public:
 
       const CounterDescription &cd = m_Descriptions[section - 1];
 
-      QString unit = QString::null;
+      QString unit = QString();
       switch(cd.unit)
       {
         case CounterUnit::Bytes: unit = lit("bytes"); break;
@@ -272,7 +272,8 @@ protected:
 
   bool lessThan(const QModelIndex &left, const QModelIndex &right) const override
   {
-    return sourceModel()->data(left, SortDataRole) < sourceModel()->data(right, SortDataRole);
+    return RDVariantLessThan(sourceModel()->data(left, SortDataRole),
+                             sourceModel()->data(right, SortDataRole));
   }
 
 private:
diff --git a/qrenderdoc/Windows/PipelineState/GLPipelineStateViewer.cpp b/qrenderdoc/Windows/PipelineState/GLPipelineStateViewer.cpp
index e29baed..2f87dbf 100644
--- a/qrenderdoc/Windows/PipelineState/GLPipelineStateViewer.cpp
+++ b/qrenderdoc/Windows/PipelineState/GLPipelineStateViewer.cpp
@@ -3939,7 +3939,7 @@ void GLPipelineStateViewer::exportHTML(QXmlStreamWriter &xml, const GLPipe::Fram
                              {
                                  tr("Read Buffer"),
                              },
-                             {fb.readFBO.readBuffer});
+                             QVariantList{fb.readFBO.readBuffer});
   }
 }
 
diff --git a/qrenderdoc/Windows/PipelineState/PipelineStateViewer.cpp b/qrenderdoc/Windows/PipelineState/PipelineStateViewer.cpp
index 13e8484..d51cdf5 100644
--- a/qrenderdoc/Windows/PipelineState/PipelineStateViewer.cpp
+++ b/qrenderdoc/Windows/PipelineState/PipelineStateViewer.cpp
@@ -162,7 +162,7 @@ void RDPreviewTooltip::paintEvent(QPaintEvent *ev)
 {
   QStylePainter p(this);
   QStyleOptionFrame opt;
-  opt.init(this);
+  opt.initFrom(this);
   p.drawPrimitive(QStyle::PE_PanelTipLabel, opt);
   p.end();
 
@@ -173,7 +173,7 @@ void RDPreviewTooltip::resizeEvent(QResizeEvent *e)
 {
   QStyleHintReturnMask frameMask;
   QStyleOption option;
-  option.init(this);
+  option.initFrom(this);
   if(style()->styleHint(QStyle::SH_ToolTip_Mask, &option, this, &frameMask))
     setMask(frameMask.region);
 
diff --git a/qrenderdoc/Windows/PixelHistoryView.cpp b/qrenderdoc/Windows/PixelHistoryView.cpp
index 41d31dc..e65b79b 100644
--- a/qrenderdoc/Windows/PixelHistoryView.cpp
+++ b/qrenderdoc/Windows/PixelHistoryView.cpp
@@ -148,7 +148,7 @@ public:
   Qt::ItemFlags flags(const QModelIndex &index) const override
   {
     if(!index.isValid())
-      return 0;
+      return Qt::NoItemFlags;
 
     return QAbstractItemModel::flags(index);
   }
@@ -731,7 +731,11 @@ void PixelHistoryView::SetFailedDebug()
 void PixelHistoryView::enableTimelineHighlight()
 {
   if(m_Ctx.HasTimelineBar())
+#if QT_VERSION >= QT_VERSION_CHECK(6, 0, 0)
+    m_Ctx.GetTimelineBar()->HighlightHistory(m_Model->texID(), m_Model->modifications());
+#else
     m_Ctx.GetTimelineBar()->HighlightHistory(m_Model->texID(), m_Model->modifications().toList());
+#endif
 }
 
 void PixelHistoryView::disableTimelineHighlight()
@@ -740,7 +744,11 @@ void PixelHistoryView::disableTimelineHighlight()
     m_Ctx.GetTimelineBar()->HighlightHistory(ResourceId(), {});
 }
 
+#if QT_VERSION >= QT_VERSION_CHECK(6, 0, 0)
+void PixelHistoryView::enterEvent(QEnterEvent *event)
+#else
 void PixelHistoryView::enterEvent(QEvent *event)
+#endif
 {
   enableTimelineHighlight();
 }
diff --git a/qrenderdoc/Windows/PixelHistoryView.h b/qrenderdoc/Windows/PixelHistoryView.h
index de98975..4248053 100644
--- a/qrenderdoc/Windows/PixelHistoryView.h
+++ b/qrenderdoc/Windows/PixelHistoryView.h
@@ -60,7 +60,11 @@ private slots:
   void on_events_doubleClicked(const QModelIndex &index);
 
 protected:
+#if QT_VERSION >= QT_VERSION_CHECK(6, 0, 0)
+  void enterEvent(QEnterEvent *event) override;
+#else
   void enterEvent(QEvent *event) override;
+#endif
   void leaveEvent(QEvent *event) override;
 
 private:
diff --git a/qrenderdoc/Windows/PythonShell.cpp b/qrenderdoc/Windows/PythonShell.cpp
index 8216c2b..3138bf7 100644
--- a/qrenderdoc/Windows/PythonShell.cpp
+++ b/qrenderdoc/Windows/PythonShell.cpp
@@ -74,7 +74,7 @@ EditorWrapper::EditorWrapper(PythonShell *parent) : QFrame(parent), m_PyShell(pa
   layout()->addWidget(m_Warning);
   layout()->addWidget(m_Scintilla);
   layout()->setSpacing(0);
-  layout()->setMargin(0);
+  layout()->setContentsMargins(0, 0, 0, 0);
   layout()->setContentsMargins(0, 0, 0, 0);
 
   setTitle(QString());
@@ -293,7 +293,11 @@ PythonShell::PythonShell(ICaptureContext &ctx, QWidget *parent)
        e->key() != Qt::Key_Down)
       return;
     ui->lineInput->setFocus(Qt::OtherFocusReason);
+#if QT_VERSION >= QT_VERSION_CHECK(6, 0, 0)
+    QApplication::postEvent(ui->lineInput, e->clone());
+#else
     QApplication::postEvent(ui->lineInput, new QKeyEvent(*e));
+#endif
   });
 
   m_ToolTip = new RDToolTip(this);
diff --git a/qrenderdoc/Windows/ResourceInspector.cpp b/qrenderdoc/Windows/ResourceInspector.cpp
index 5ec9b1f..6442389 100644
--- a/qrenderdoc/Windows/ResourceInspector.cpp
+++ b/qrenderdoc/Windows/ResourceInspector.cpp
@@ -74,7 +74,7 @@ public:
   Qt::ItemFlags flags(const QModelIndex &index) const override
   {
     if(!index.isValid())
-      return 0;
+      return Qt::NoItemFlags;
 
     return QAbstractItemModel::flags(index);
   }
@@ -464,7 +464,7 @@ void ResourceInspector::RevealParameter(SDObject *param)
         if(current->GetChild(i) == next)
         {
           current = next;
-          item = parent.child((int)i, 0);
+          item = parent.model()->index((int)i, 0, parent);
           break;
         }
       }
@@ -746,7 +746,11 @@ void ResourceInspector::resourceUsage_contextMenu(const QPoint &pos)
   RDDialog::show(&contextMenu, ui->resourceUsage->viewport()->mapToGlobal(pos));
 }
 
+#if QT_VERSION >= QT_VERSION_CHECK(6, 0, 0)
+void ResourceInspector::enterEvent(QEnterEvent *event)
+#else
 void ResourceInspector::enterEvent(QEvent *event)
+#endif
 {
   HighlightUsage();
 }
diff --git a/qrenderdoc/Windows/ResourceInspector.h b/qrenderdoc/Windows/ResourceInspector.h
index 9ea814c..ab058b2 100644
--- a/qrenderdoc/Windows/ResourceInspector.h
+++ b/qrenderdoc/Windows/ResourceInspector.h
@@ -112,7 +112,11 @@ private slots:
   void resourceUsage_SplitByMarker_toggled();
 
 protected:
+#if QT_VERSION >= QT_VERSION_CHECK(6, 0, 0)
+  void enterEvent(QEnterEvent *event) override;
+#else
   void enterEvent(QEvent *event) override;
+#endif
   void showEvent(QShowEvent *event) override;
 
 private:
diff --git a/qrenderdoc/Windows/ShaderViewer.cpp b/qrenderdoc/Windows/ShaderViewer.cpp
index fd70990..64b08dd 100644
--- a/qrenderdoc/Windows/ShaderViewer.cpp
+++ b/qrenderdoc/Windows/ShaderViewer.cpp
@@ -291,7 +291,7 @@ ShaderViewer::ShaderViewer(ICaptureContext &ctx, QWidget *parent)
 
     QVBoxLayout *framelayout = new QVBoxLayout(m_DisassemblyFrame);
     framelayout->setSpacing(0);
-    framelayout->setMargin(0);
+    framelayout->setContentsMargins(0, 0, 0, 0);
     framelayout->addWidget(m_DisassemblyToolbar);
     framelayout->addWidget(m_DisassemblyView);
 
diff --git a/qrenderdoc/Windows/TextureViewer.cpp b/qrenderdoc/Windows/TextureViewer.cpp
index 95a7090..05e1db2 100644
--- a/qrenderdoc/Windows/TextureViewer.cpp
+++ b/qrenderdoc/Windows/TextureViewer.cpp
@@ -474,6 +474,7 @@ TextureViewer::TextureViewer(ICaptureContext &ctx, QWidget *parent)
       m_Ctx(ctx),
       m_Following(*this, FollowType::OutputColor, ShaderStage::Pixel, 0, 0)
 {
+  m_CustomShaderTimer.start();
   ui->setupUi(this);
 
   ui->render->SetContext(m_Ctx);
@@ -705,7 +706,11 @@ TextureViewer::~TextureViewer()
   delete ui;
 }
 
+#if QT_VERSION >= QT_VERSION_CHECK(6, 0, 0)
+void TextureViewer::enterEvent(QEnterEvent *event)
+#else
 void TextureViewer::enterEvent(QEvent *event)
+#endif
 {
   HighlightUsage();
 }
@@ -984,7 +989,7 @@ void TextureViewer::UI_UpdateStatusText()
   {
     QPalette Pal(palette());
 
-    Pal.setColor(QPalette::Background, swatchColor);
+    Pal.setColor(QPalette::Window, swatchColor);
 
     ui->pickSwatch->setAutoFillBackground(true);
     ui->pickSwatch->setPalette(Pal);
@@ -2639,13 +2644,17 @@ void TextureViewer::thumb_clicked(QMouseEvent *e)
 
 void TextureViewer::render_mouseWheel(QWheelEvent *e)
 {
+#if QT_VERSION >= QT_VERSION_CHECK(5, 14, 0)
+  QPoint cursorPos = e->position().toPoint();
+#else
   QPoint cursorPos = e->pos();
+#endif
 
   setFitToWindow(false);
 
   // scroll in logarithmic scale
   double logScale = logf(m_TexDisplay.scale);
-  logScale += e->delta() / 2500.0;
+  logScale += e->angleDelta().y() / 2500.0;
   UI_SetScale((float)expf(logScale), cursorPos.x() * ui->render->devicePixelRatioF(),
               cursorPos.y() * ui->render->devicePixelRatioF());
 
@@ -3017,7 +3026,7 @@ void TextureViewer::Reset()
   {
     QPalette Pal(palette());
 
-    Pal.setColor(QPalette::Background, Qt::black);
+    Pal.setColor(QPalette::Window, Qt::black);
 
     ui->pickSwatch->setAutoFillBackground(true);
     ui->pickSwatch->setPalette(Pal);
diff --git a/qrenderdoc/Windows/TextureViewer.h b/qrenderdoc/Windows/TextureViewer.h
index c8d0db2..a94d987 100644
--- a/qrenderdoc/Windows/TextureViewer.h
+++ b/qrenderdoc/Windows/TextureViewer.h
@@ -25,6 +25,7 @@
 #pragma once
 
 #include <QDir>
+#include <QElapsedTimer>
 #include <QFrame>
 #include <QMenu>
 #include <QMouseEvent>
@@ -235,7 +236,11 @@ private slots:
   void channelsWidget_toggled(bool checked) { UI_UpdateChannels(); }
   void channelsWidget_selected(int index) { UI_UpdateChannels(); }
 protected:
+#if QT_VERSION >= QT_VERSION_CHECK(6, 0, 0)
+  void enterEvent(QEnterEvent *event) override;
+#else
   void enterEvent(QEvent *event) override;
+#endif
   void showEvent(QShowEvent *event) override;
 
 private:
@@ -373,7 +378,7 @@ private:
 
   rdcarray<DescriptorThumbUpdate> m_DescriptorThumbUpdates;
 
-  QTime m_CustomShaderTimer;
+  QElapsedTimer m_CustomShaderTimer;
   int m_CustomShaderWriteTime = 0;
 
   QFileSystemWatcher *m_Watcher = NULL;
diff --git a/qrenderdoc/Windows/TimelineBar.cpp b/qrenderdoc/Windows/TimelineBar.cpp
index e4fb683..dc50f74 100644
--- a/qrenderdoc/Windows/TimelineBar.cpp
+++ b/qrenderdoc/Windows/TimelineBar.cpp
@@ -428,7 +428,7 @@ void TimelineBar::mouseMoveEvent(QMouseEvent *e)
 
 void TimelineBar::wheelEvent(QWheelEvent *e)
 {
-  float mod = (1.0 + e->delta() / 2500.0f);
+  float mod = (1.0 + e->angleDelta().y() / 2500.0f);
 
   qreal prevZoom = m_zoom;
 
@@ -439,9 +439,15 @@ void TimelineBar::wheelEvent(QWheelEvent *e)
   // adjust the pan so that it's still in bounds, and so the zoom acts centred on the mouse
   qreal newPan = m_pan;
 
-  newPan -= (e->x() - m_eidAxisRect.left());
+#if QT_VERSION >= QT_VERSION_CHECK(5, 14, 0)
+  const qreal wheelX = e->position().x();
+#else
+  const qreal wheelX = e->x();
+#endif
+
+  newPan -= (wheelX - m_eidAxisRect.left());
   newPan = newPan * zoomDelta;
-  newPan += (e->x() - m_eidAxisRect.left());
+  newPan += (wheelX - m_eidAxisRect.left());
 
   m_pan = qBound(-m_dataArea.width() * (m_zoom - 1.0), newPan, 0.0);
 
diff --git a/qrenderdoc/qrenderdoc.pro b/qrenderdoc/qrenderdoc.pro
index dabf69d..453cd8b 100644
--- a/qrenderdoc/qrenderdoc.pro
+++ b/qrenderdoc/qrenderdoc.pro
@@ -134,7 +134,16 @@ win32 {
 	SOURCES += $$CMAKE_DIR/qrenderdoc/qrenderdoc_python.cxx
 
 	CONFIG += warn_off
-	CONFIG += c++14
+	# Qt 6 ignores any request below C++17, which would leave the standard
+	# up to the compiler's default
+	equals(QT_MAJOR_VERSION, 5) {
+		CONFIG += c++14
+	} else {
+		CONFIG += c++17
+		# scintilla converts text with QTextCodec, which Qt 6 moved into the
+		# Qt5Compat module
+		QT += core5compat
+	}
 	QMAKE_CFLAGS_WARN_OFF -= -w
 	QMAKE_CXXFLAGS_WARN_OFF -= -w
 
@@ -158,7 +167,7 @@ win32 {
 		QMAKE_POST_LINK += ln -sf $$[QT_INSTALL_PLUGINS] $${QTPLUGINS_PATH} ;
 		QMAKE_POST_LINK += sh $$_PRO_FILE_PWD_/../util/set_plist_version.sh $${RENDERDOC_VERSION}.0 $${INFO_PLIST_PATH}
 	} else {
-		QT += x11extras
+		equals(QT_MAJOR_VERSION, 5): QT += x11extras
 		DEFINES += RENDERDOC_PLATFORM_POSIX RENDERDOC_PLATFORM_LINUX RENDERDOC_WINDOWING_XLIB RENDERDOC_WINDOWING_XCB
 		QMAKE_LFLAGS += '-Wl,--no-as-needed -rdynamic'
 	}
diff --git a/renderdoc/api/replay/rdcarray.h b/renderdoc/api/replay/rdcarray.h
index 0422fc3..904bbbd 100644
--- a/renderdoc/api/replay/rdcarray.h
+++ b/renderdoc/api/replay/rdcarray.h
@@ -841,6 +841,8 @@ public:
     return *this;
   }
 
+#if QT_VERSION < QT_VERSION_CHECK(6, 0, 0)
+  // in Qt6 QVector is an alias of QList, so these would be duplicates
   rdcarray(const QVector<T> &in)
   {
     elems = NULL;
@@ -865,6 +867,7 @@ public:
     return *this;
   }
 #endif
+#endif
 };
 
 // fixed size array, wrapped to be more python-friendly (mapped to an N-tuple)
diff --git a/renderdoc/api/replay/rdcstr.h b/renderdoc/api/replay/rdcstr.h
index caf358e..e7d65f9 100644
--- a/renderdoc/api/replay/rdcstr.h
+++ b/renderdoc/api/replay/rdcstr.h
@@ -941,6 +941,14 @@ inline rdcstr operator+(const QString &left, const rdcstr &right)
   return rdcstr(left) += right;
 }
 
+// Qt 6 added QString::operator+=(QUtf8StringView), which an rdcstr converts to
+// just as readily as it does to QString. Take the ambiguity away with an exact
+// match.
+inline QString &operator+=(QString &left, const rdcstr &right)
+{
+  return left += QString(right);
+}
+
 inline rdcstr operator+(const QChar &left, const rdcstr &right)
 {
   return rdcstr(left) += right;
@@ -1171,6 +1179,26 @@ public:
 #endif
 };
 
+#if defined(RENDERDOC_QT_COMPAT)
+// as for rdcstr, take away the QString/QUtf8StringView ambiguity Qt 6 creates
+inline QString &operator+=(QString &left, const rdcinflexiblestr &right)
+{
+  return left += QString(right);
+}
+
+// likewise, concatenating onto an rdcinflexiblestr only went through QString,
+// and Qt 6 added an rvalue operator+ that ties with the const reference one
+inline rdcstr operator+(const rdcinflexiblestr &left, const rdcstr &right)
+{
+  return rdcstr(left) += right;
+}
+
+inline rdcstr operator+(const rdcinflexiblestr &left, const char *const right)
+{
+  return rdcstr(left) += right;
+}
+#endif
+
 // add a std::hash overload so rdcstr can be used in hashmaps
 #ifdef RENDERDOC_EXPORTS