Release note

Qt 6.4.2 release is a patch release made on the top of Qt 6.4.1.
As a patch release, Qt 6.4.2 does not add any new functionality but provides
bug fixes and other improvements and maintains both forward and backward
compatibility (source and binary) with Qt 6.4.1.

For detailed information about Qt 6.4, refer to the online documentation
included in this distribution. The documentation is also available online:

https://doc.qt.io/qt-6/index.html

The Qt version 6.4 series is binary compatible with the 6.3.x series.
Applications compiled for 6.3 will continue to run with 6.4.

Some of the changes listed in this file include issue tracking numbers
corresponding to tasks in the Qt Bug Tracker:

https://bugreports.qt.io/

Each of these identifiers can be entered in the bug tracker to obtain
more information about a particular change.

To make it easier to port to Qt 6, we have created a porting guide to
summarize those changes and provide guidance to handle them. In the
guide, you can find links to articles about changes that may affect your
application and help you transition from Qt 5.15 to Qt 6:

https://doc.qt.io/qt-6/portingguide.html

Important Changes

qtbase

04f6f4afa9 Update bundled zlib to version 1.2.13
zlib was updated to version 1.2.13.
ff52558530 Update bundled libpng to version 1.6.39
libpng was updated to version 1.6.39

qtdeclarative

2b258e019e QQuickNinePatchImage: fix aliasing by respecting the smooth
property
The Imagine style now supports smooth scaling for 9-patch images when
the QT_QUICK_CONTROLS_IMAGINE_SMOOTH environment variable is set to 1.

Fixes

qtbase

QTBUG-108128 Absolute coordinates used for pointer events on wasm
QTBUG-106031 Mouse cursor location offset if canvas doesn't start at
0,0
QTBUG-107687 [REG 6.3.1 -> 6.3.2] qt_add_resources with .qm
translation files no longer rebuild generated .qrc when .qm files change
QTBUG-108113 "RCC: Cannot find file" in qt_add_translations
QTBUG-103470 [iOS] CMake translation handling fails
QTBUG-108103 QHostAddress::isEqual() with IPv6 determines valid ip to
be any
QTBUG-46681 [REG 4.x->5.x] QPainter in paintEvent() doesn't work with
Qt::WA_PaintOnScreen
QTBUG-100085 xcb: Native window does not get paint event if another
window on top of it is hidden unless there is a enter/leave event
somewhere
QTBUG-63324 iOS/macOS: system localization always returns english
language
QTBUG-108186 Crash in qt_memrotate90 or qt_memrotate270
QTBUG-108156 Unhandled exception on QNetworkInformation::load()
QTBUG-89156 [REG 5.15.0->5.15.1] Focus is limitted after reparenting
and adding widgets
QTBUG-108196 SecKeychain is deprecated [-Wdeprecated-declarations]
when compiling qnetworkaccessmanager.cpp
QTBUG-67579 QT5 apps running natively under Wayland do not respect
cursor size setting
QTBUG-87778 wayland: cursor size wrong
QTBUG-108194 FAIL! : data::tst_simulation-behavior::compile() module
"Simu" is not installed
QTBUG-108047 Setting macos style before creating a QApplication
crashes
QTBUG-108218 [Win] Access violation in QNetworkListManagerEvents
QTBUG-107572 Expose QLineEdit focus for QComboBox editable
QTBUG-108344 Something is rotten with texture-based widgets that are
native child widgets or are children of a native child widget
QTBUG-108277 QWidget::setParent calls q_evaluateRhiRecursive which is
slow
QTBUG-105017 Crash in QRhiGles2::ensureContext with
QT_WIDGETS_RHI_BACKEND=vulkan and QOpenGLWidget
QTBUG-106583 Windows and dialogs flashing white
QTBUG-108382 One more unhandled exception on
QNetworkInformation::load()
QTBUG-108311 [REG: 6.3->6.4]: When moving a QDockWidget under certain
environments it will trigger a warning message
QTBUG-106920 MOC cannot parse nested inline namespace (Parse error at
"::")
QTBUG-108742 macdeployqt: Multimedia plugins missing
QTBUG-107057 macdeployqt does not include libdarwinmediaplugin.dylib
QTBUG-108605 Unhandled WinRT exception at
QSystemLocalePrivate::uiLanguages()
QTBUG-105857 Qt application does not follow the DPI change when the
DPI setting is changed before showing the first window
QTBUG-108709 [REG 6.4.0 -> 6.4.1] Second ColorRole change via
QPalette:setBrush() does not modify cacheKey
QTBUG-107675 Typo in the document?
QTBUG-107806 Link is dead in the document
QTBUG-68175 tst_QWidget::raise is flaky
QTBUG-108743 QColor - Undefined symbols QColor::QColor(char const*),
QColor::QColor(QString const&)...
QTBUG-108662 Can't build for Android
QTBUG-106025 REG: isSignalConnected creates a dead lock.
QTBUG-108764 tst_qwidgetrepaintmanager is flaky
QTBUG-108300 Crash when setPersistentGraphics(false),
setPersistentSceneGraph(false) and visible: true on wayland
QTBUG-108677 macdeployqt tool does not copy networkinformation plugin
QTBUG-83185 [Android]: When using night or dark mode on a device, then
the style extracted is still set as if it is light mode
QTBUG-87137 tst_QApplication::sendEventsOnProcessEvents() failed on
Ubuntu 20.04/22.04 and RHEL 9
QTBUG-91255 [Android] Add support for APK Signature Scheme v2
QTBUG-108175 [macOS] Qt warning: "macOS generated a color-profile Qt
couldn't parse. This shouldn't happen."
QTBUG-105735 Focus is not set to a child widget when a modal is open
QTBUG-107604 [Reg 5.15.10 -> 5.15.11] Incorrect fullscreen dimensions
on some Android devices
QTBUG-107709 Android screen size mismatch [Reg 5.15.10 -> 5.15.11]
QTBUG-107523 [REG 5.15.10 -> 5.15.11] Android edge-to-edge layout
broken
QTBUG-92468 QTextEdit cursor is drawn incorrectly
QTBUG-86823 REG: Blinking cursor leaving an artifact in QTextEdit
QTBUG-96288 QTextEdit cursor postion error when QTextEdit has
different pointsize
QTBUG-109036 QImage mismatch in QXcbBackingStore
QTBUG-106906 tst_qtcuncurrentrun::pollForIsFinished occasionally
crashes
QTBUG-108815 Installing qtdeclarative fails
QTBUG-103611 [Reg 5.15 -> 6.x] Re-initializing QGuiApplication causes
QQmlApplicationEngine to crash
QTBUG-106393 Mac OS: Dot and Comma key combinations not working for
russian layout

qtdeclarative

QTBUG-108026 Memory leak when capturing a 3D scene using
QQuickItem::grabImage
QTBUG-106106 Crash in ~QQuickScrollBarAttached during rearrange of
QQmlDelegateModel
QTBUG-71922 Mime data is corrupted when using QQuickDragAttached and
it's not UTF-8
QTBUG-106940 "QML Import could not be resolved in any of the import
paths: shared" when trying to QML debug example "emitters"
QTBUG-74496 Performance issue: rejected drag re-triggers drag enter
event every frame while mouse moves
QTBUG-107989 Aliasing occurs at the image boundary if add Scale
Animator to nine-patch image
QTBUG-107818 Sometimes ShaderEffect types are not be drawn correctly
on 2 QQuickWindows
QTBUG-108252 Crash occurs when GUI thread accesses QRhi objects
created by Renderer Thread
QTBUG-98979 ListView scrolling is broken for ListView.SnapOneItem mode
QTBUG-107774 madvise() terminates application due to EBADF code
QTBUG-106602 extending-qml example is missing QtQuick dependency in
CMakeLists.txt
QTBUG-106884 Typo in the document
QTBUG-94619 Qt.labs.platform.Menu opens at the wrong location with
scaling enabled
QTBUG-94783 Popup menu in incorrect position when using
QT_SCALE_FACTOR=1.5 on Wayland Ubuntu
QTBUG-108298 Crash using ConicalGradient in a ShapePath
QTBUG-108352 tst_touchmouse::strayTouchDoesntAutograb is flaky
QTBUG-108549 PinchHandler.scale loses the accumulated scaling if
target == null
QTBUG-92064 PinchHandler target scale jumps when pinching a second
time via native gesture
QTBUG-104890 PointHandler deactivated on touch screen
QTBUG-108627 Assertion in QQmlPropertyData::setOverrideIndex
QTBUG-106875 Segfault when Loader is trying to load a file that
contains the Loader
QTBUG-108646 Segmentation fault when inspecting QML objects without
breaking
QTBUG-83890 [REG 5.14.1->5.14.2,5.15] Horizontal Scrollbars in
ScrollView when Flickable fits
QTBUG-108388 code snippet in the document is incomplete
QTBUG-108820 Infinity - real vs int
QTBUG-108634 Invalid code generated for comparison
QTBUG-108651 Property change detection for null values doesn't seem to
be working
QTBUG-108683 [Reg 5.15.2/6.3.2 -> 6.4.x] DropShadow: Changing radius
at runtime also changes Z-order
QTBUG-107607 Crash when trying to inspect "this.parent"
QTBUG-108913 ->6.4.1: Restore qmllint JSON Output Message
QTBUG-108697 Program can crash when Connections target is destroyed
QTBUG-109010 top-level build: automoc broken yet again in 6.4 branch
(depending on moc before it's built)
QTBUG-104047 Qt Quick: Drag event coordinates wrong in Release mode
QTBUG-104716 draganddrop example issues
QTBUG-109002 [PinchHandler] Dragging a target is not functional
QTBUG-107171 qmlsc: Cannot resolve type annotations for args of type
list
QTBUG-98130 QtQuick and controls examples use qt_add_resources to add
QML files
QTBUG-107850 Crash on QQuickItem destruction
QTBUG-106864 Reg-5.15.9->5.15.10: Android crash on startup on armv7
(32bit) devices
QTBUG-106269 Qt Quick apps immediately crash under Android 6

qtmultimedia

QTBUG-108009 QML Camera maximumZoomFactor in iPad
QTBUG-108027 Signal videoFrameChanged not emitted
QTBUG-95127 QMediaPlayer::setVideoOutput() no longer takes QList of
outputs
QTBUG-103238 [macOS] Crash in qt_convert_NV12_to_ARGB32
QTBUG-107671 Using strcmp instead of gst's methods for classfying
classes
QTBUG-108187 QAudioSink can not be moved to another thread
QTBUG-108898 [Windows] Crash on
QWindowsMediaDevices::availableDevices()
QTBUG-109009 Ffmpeg: videotoolbox doesn't support some yuv 8bit
formats
QTBUG-107678 audio device has unknown channel
QTBUG-108020 QMediaDevices on MacOS needs additional listeners to
correctly catch device changes
QTBUG-108018 Camera Example crashes on macOS 13 ventura
QTBUG-103567 QML MediaPlayer fails to playback rtsp media properly.

qttools

QTBUG-108243 Naming menu separators in design view is broken
QTBUG-94365 QDoc: "error code: 4" from clang on macOS
QTBUG-108353 qdoc: QHash related warnings with LLVM 15.0.0
QTBUG-96239 Document CMake component in CMake function documentation

qtdoc

QTBUG-108513 Disappearing text on a Button on QtQuick Controls when
the Dark theme is active on macOS
QTBUG-108101 String "6.4.0" found in Qt6.4.1 sources
QTBUG-108670 doc state, that QOpenGLWidget is not supported, but it
was fixed in qt 6.4
QTBUG-108335 calqlatr demo buttons are broken

qtwayland

QTBUG-104259 tst_seatv4 tests are failing with Ubuntu 22.04 Wayland
QTBUG-75919 Override cursor has no precedence on Wayland

qt3d

QTBUG-56368 Crash when using async NodeInstantiator within Scene3D
QTBUG-106972 QRenderCapture leaks memory with RHI renderer
QTBUG-107693 tst_QResourceManager received signal 11 (SIGSEGV) with
Ubuntu 22.04 QEMU

qtserialbus

QTBUG-107132 Typo in the document?

qtwebsockets

QTBUG-108276 MQTT WebSocket doesn't connect

qtwebengine

QTBUG-108265 Pasting plain text does not work on Discord web
QTBUG-108843 [WebRTC] Crash inside
RTCStatsCollector::ProduceAudioRTPStreamStats_n

qtvirtualkeyboard

QTBUG-108030 Virtual keyboard basic example freezes on Android
QTBUG-108396 The link in the document seems to be wrong

qtspeech

QTBUG-108381 qtspeech does not compile without qtqml
QTBUG-108205 tst_QTextToSpeech::pauseResume(darwin) fails on macOS 13
in CI

qtquick3d

QTBUG-108078 CustomMaterial texture min filter can't be changed
QTBUG-96302 3D scenes with 2D subtrees leak graphics resources upon
destroying the scene
QTBUG-106032 If you start an application with View3D not visible from
one state, it's impossible to get it visible then.
QTBUG-86716 Materials shared between views don't always render
QTBUG-108811 Skinned mesh doesn't follow skeleton
QTBUG-108606 All View3D instances where material is used are not
updated when material color changes
QTBUG-107780 Rendering Texture in WebAssembly
QTBUG-107841 tst_Input crashes a lot
QDS-8024 Icons needed for new component library items
QTBUG-109157 QtQuick3D fails to compile with C++20 : allocator.destroy
called in qtquick3d/src/3rdparty/embree//common/sys/vector.h:137

qtshadertools

QTBUG-107483 Typo in the document?

qtmqtt

QTBUG-108276 MQTT WebSocket doesn't connect

qtquick3dphysics

QTBUG-108897 QFATAL : tst_physicsscene::UnknownTestFunc() ASSERT
QTBUG-108667 libcooker installed in PREFIX/bin

Known Issues

Check that your system meets Qt's requirements:
https://doc.qt.io/qt-6.4/supported-platforms.html
RTA reported issues from Qt 6.4
https://bugreports.qt.io/issues/?filter=24174
See Qt 6.4 known issues from:
https://wiki.qt.io/Qt_6.4_Known_Issues

Credits for the release goes to:

Eirik Aavitsland
Laszlo Agocs
Vladimir Belyavsky
Nicholas Bennett
Tim Blechmann
Mikolaj Boc
Joerg Bornemann
Assam Boudjelthia
Aurélien Brooke
Michael Brüning
Hxcan Cai
Alexandru Croitor
Mitch Curtis
Thibaut Cuvelier
Giuseppe D'Angelo
Artem Dyomin
Alexey Edelev
Oliver Eftevaag
Hatem ElKharashy
Andreas Eliasson
Ilya Fedin
Nicolas Fella
Josep M. Ferrer
Jan Grulich
Richard Moe Gustavsen
Lucie Gérard
Tang Haixiang
Heikki Halmet
Jani Heikkinen
Miikka Heikkinen
Ulf Hermann
Volker Hilsheimer
Allan Sandfeld Jensen
Jonas Karlsson
Johannes Kauffmann
Timothée Keller
Friedemann Kleint
Michal Klocek
Jarkko Koivikko
Janne Koskinen
Fabian Kosmale
Konrad Kujawa
Santhosh Kumar
Kai Köhne
Inho Lee
Paul Lemire
Thiago Macieira
Ievgenii Meshcheriakov
Phan Quang Minh
Samuel Mira
Fawzi Mohamed
Bartlomiej Moskal
Marc Mutz
Mårten Nordheim
Dennis Oberst
Bumjoon Park
Evgen Pervenenko
Samuli Piippo
Timur Pocheptsov
Milla Pohjanheimo
Lorn Potter
Liang Qi
David Redondo
Topi Reinio
Alexey Rochev
Niclas Rosenvik
Shawn Rutledge
Sami Shalayel
Axel Spoerl
Piotr Srebrny
Christian Stenger
Christian Strømme
Tasuku Suzuki
Jan Arve Sæther
Morten Sørvig
U-GER\tjmaciei
Peter Varga
Doris Verria
Tor Arne Vestbø
Ville Voutilainen
Ole Wegen
Edward Welbourne
Fushan Wen
Oliver Wolff
Semih Yavuz
Vlad Zahorodnii
Yuhang Zhao