qt.qpa.plugin: Could not load the Qt platform plugin "xcb" in "" even though it was found.

SGaist

Check whether there's Qt libraries in your matlab installation.

phil-lipp

I hope someone on this forum can help me. I'm trying to use Howdy (https://github.com/boltgolt/howdy), but I get the error described by OP.
I only get the error when I use su -, however when I use plain su (without the -) it works. So I think i somehow messed up the install when I forgot to add the -... how can I fix this?

the error:

qt.qpa.xcb: could not connect to display 
qt.qpa.plugin: Could not load the Qt platform plugin "xcb" in "" even though it was found.
This application failed to start because no Qt platform plugin could be initialized. Reinstalling the application may fix this problem.
``

JonB

@phil-lipp
https://forum.qt.io/post/763171 was just asked.

MarsOnMart

I had too problems with this file.
It just depends from which shared file left you.
first at all set in the console :

export QT_DEBUG_PLUGINS=1

This will show you in which part it fails, normally is in libqxcb.so,

example:
python main.py

qt.core.plugin.factoryloader: checking directory path "/home/user/.local/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms" ...
qt.core.plugin.factoryloader: looking at "/home/user/.local/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqwayland-generic.so"
qt.core.plugin.loader: Found metadata in lib /home/user/.local/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqwayland-generic.so, metadata=
{
    "IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3",
    "MetaData": {
        "Keys": [
            "wayland"
        ]
    },
    "archlevel": 1,
    "className": "QWaylandIntegrationPlugin",
    "debug": false,
    "version": 394496
}


qt.core.plugin.factoryloader: Got keys from plugin meta data QList("wayland")
qt.core.plugin.factoryloader: looking at "/home/user/.local/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqminimal.so"
qt.core.plugin.loader: Found metadata in lib /home/user/.local/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqminimal.so, metadata=
{
    "IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3",
    "MetaData": {
        "Keys": [
            "minimal"
        ]
    },
    "archlevel": 1,
    "className": "QMinimalIntegrationPlugin",
    "debug": false,
    "version": 394496
}


qt.core.plugin.factoryloader: Got keys from plugin meta data QList("minimal")
qt.core.plugin.factoryloader: looking at "/home/user/.local/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqeglfs.so"
qt.core.plugin.loader: Found metadata in lib /home/user/.local/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqeglfs.so, metadata=
{
    "IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3",
    "MetaData": {
        "Keys": [
            "eglfs"
        ]
    },
    "archlevel": 1,
    "className": "QEglFSIntegrationPlugin",
    "debug": false,
    "version": 394496
}


qt.core.plugin.factoryloader: Got keys from plugin meta data QList("eglfs")
qt.core.plugin.factoryloader: looking at "/home/user/.local/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqwayland-egl.so"
qt.core.plugin.loader: Found metadata in lib /home/user/.local/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqwayland-egl.so, metadata=
{
    "IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3",
    "MetaData": {
        "Keys": [
            "wayland-egl"
        ]
    },
    "archlevel": 1,
    "className": "QWaylandEglPlatformIntegrationPlugin",
    "debug": false,
    "version": 394496
}


qt.core.plugin.factoryloader: Got keys from plugin meta data QList("wayland-egl")
qt.core.plugin.factoryloader: looking at "/home/user/.local/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqoffscreen.so"
qt.core.plugin.loader: Found metadata in lib /home/user/.local/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqoffscreen.so, metadata=
{
    "IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3",
    "MetaData": {
        "Keys": [
            "offscreen"
        ]
    },
    "archlevel": 1,
    "className": "QOffscreenIntegrationPlugin",
    "debug": false,
    "version": 394496
}


qt.core.plugin.factoryloader: Got keys from plugin meta data QList("offscreen")
qt.core.plugin.factoryloader: looking at "/home/user/.local/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqlinuxfb.so"
qt.core.plugin.loader: Found metadata in lib /home/user/.local/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqlinuxfb.so, metadata=
{
    "IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3",
    "MetaData": {
        "Keys": [
            "linuxfb"
        ]
    },
    "archlevel": 1,
    "className": "QLinuxFbIntegrationPlugin",
    "debug": false,
    "version": 394496
}


qt.core.plugin.factoryloader: Got keys from plugin meta data QList("linuxfb")
qt.core.plugin.factoryloader: looking at "/home/user/.local/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqvnc.so"
qt.core.plugin.loader: Found metadata in lib /home/user/.local/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqvnc.so, metadata=
{
    "IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3",
    "MetaData": {
        "Keys": [
            "vnc"
        ]
    },
    "archlevel": 1,
    "className": "QVncIntegrationPlugin",
    "debug": false,
    "version": 394496
}


qt.core.plugin.factoryloader: Got keys from plugin meta data QList("vnc")
qt.core.plugin.factoryloader: looking at "/home/user/.local/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqvkkhrdisplay.so"
qt.core.plugin.loader: Found metadata in lib /home/user/.local/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqvkkhrdisplay.so, metadata=
{
    "IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3",
    "MetaData": {
        "Keys": [
            "vkkhrdisplay"
        ]
    },
    "archlevel": 1,
    "className": "QVkKhrDisplayIntegrationPlugin",
    "debug": false,
    "version": 394496
}


qt.core.plugin.factoryloader: Got keys from plugin meta data QList("vkkhrdisplay")
qt.core.plugin.factoryloader: looking at "/home/user/.local/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqminimalegl.so"
qt.core.plugin.loader: Found metadata in lib /home/user/.local/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqminimalegl.so, metadata=
{
    "IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3",
    "MetaData": {
        "Keys": [
            "minimalegl"
        ]
    },
    "archlevel": 1,
    "className": "QMinimalEglIntegrationPlugin",
    "debug": false,
    "version": 394496
}


qt.core.plugin.factoryloader: Got keys from plugin meta data QList("minimalegl")
qt.core.plugin.factoryloader: looking at "/home/user/.local/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqxcb.so"
qt.core.plugin.loader: Found metadata in lib /home/user/.local/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqxcb.so, metadata=
{
    "IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3",
    "MetaData": {
        "Keys": [
            "xcb"
        ]
    },
    "archlevel": 1,
    "className": "QXcbIntegrationPlugin",
    "debug": false,
    "version": 394496
}


qt.core.plugin.factoryloader: Got keys from plugin meta data QList("xcb")
qt.core.plugin.factoryloader: checking directory path "/usr/bin/platforms" ...
qt.core.library: "/home/user/.local/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqxcb.so" cannot load: Cannot load library /home/user/.local/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqxcb.so: (libxcb-cursor.so.0: cannot open shared object file: No such file or directory)
qt.core.plugin.loader: QLibraryPrivate::loadPlugin failed on "/home/user/.local/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqxcb.so" : "Cannot load library /home/user/.local/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqxcb.so: (libxcb-cursor.so.0: cannot open shared object file: No such file or directory)"
qt.qpa.plugin: Could not load the Qt platform plugin "xcb" in "" even though it was found.
This application failed to start because no Qt platform plugin could be initialized. Reinstalling the application may fix this problem.

Available platform plugins are: wayland, minimal, eglfs, wayland-egl, offscreen, linuxfb, vnc, vkkhrdisplay, minimalegl, xcb.

zsh: IOT instruction  python main.py

And this error occurs when some of the shared libraries are not found.
In my case was the :
"/usr/bin/platforms" ...
qt.core.library: "/home/user/.local/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqxcb.so" cannot load: Cannot load library /home/user/.local/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqxcb.so:

== =>(libxcb-cursor.so.0: cannot open shared object file: No such file or directory) <===

qt.core.plugin.loader: QLibraryPrivate::loadPlugin failed on "/home/user/.local/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqxcb.so" : "Cannot load library /home/user/.local/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqxcb.so: (libxcb-cursor.so.0: cannot open shared object file: No such file or directory)"
.
This is the shared library that lefts , it could that does not be the only one , so for see better which shared libraries are and which not use the next command :

ldd : /home/user/.local/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqxcb.so

This must show you the next thing :

::
ldd: ./:: No such file or directory
/home/user/.local/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqxcb.so:
        linux-vdso.so.1 (0x00007fff8b5b6000)
        libQt6XcbQpa.so.6 => /home/user/.local/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/../../lib/libQt6XcbQpa.so.6 (0x00007febd8bec000)
        libxkbcommon-x11.so.0 => /lib/x86_64-linux-gnu/libxkbcommon-x11.so.0 (0x00007febd8bc3000)
        libxkbcommon.so.0 => /lib/x86_64-linux-gnu/libxkbcommon.so.0 (0x00007febd8b7d000)
        libxcb-cursor.so.0 => not found
        libxcb-icccm.so.4 => /lib/x86_64-linux-gnu/libxcb-icccm.so.4 (0x00007febd8b76000)
        libxcb-image.so.0 => /lib/x86_64-linux-gnu/libxcb-image.so.0 (0x00007febd8b6e000)
        libxcb-keysyms.so.1 => /lib/x86_64-linux-gnu/libxcb-keysyms.so.1 (0x00007febd8800000)
        libxcb-randr.so.0 => /lib/x86_64-linux-gnu/libxcb-randr.so.0 (0x00007febd8b5d000)
        libxcb-render-util.so.0 => /lib/x86_64-linux-gnu/libxcb-render-util.so.0 (0x00007febd8400000)
        libxcb-shm.so.0 => /lib/x86_64-linux-gnu/libxcb-shm.so.0 (0x00007febd8b58000)
        libxcb-sync.so.1 => /lib/x86_64-linux-gnu/libxcb-sync.so.1 (0x00007febd8b50000)
        libxcb-xfixes.so.0 => /lib/x86_64-linux-gnu/libxcb-xfixes.so.0 (0x00007febd8b45000)
        libxcb-render.so.0 => /lib/x86_64-linux-gnu/libxcb-render.so.0 (0x00007febd8b37000)
        libxcb-shape.so.0 => /lib/x86_64-linux-gnu/libxcb-shape.so.0 (0x00007febd8b32000)
        libxcb-xkb.so.1 => /lib/x86_64-linux-gnu/libxcb-xkb.so.1 (0x00007febd8b15000)
        libxcb.so.1 => /lib/x86_64-linux-gnu/libxcb.so.1 (0x00007febd8aeb000)
        libQt6OpenGL.so.6 => /home/user/.local/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/../../lib/libQt6OpenGL.so.6 (0x00007febd8a4a000)
        libQt6Gui.so.6 => /home/user/.local/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/../../lib/libQt6Gui.so.6 (0x00007febd7a00000)
        libGL.so.1 => /lib/x86_64-linux-gnu/libGL.so.1 (0x00007febd8779000)
        libQt6Core.so.6 => /home/user/.local/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/../../lib/libQt6Core.so.6 (0x00007febd7200000)
        libX11-xcb.so.1 => /lib/x86_64-linux-gnu/libX11-xcb.so.1 (0x00007febd8a43000)
        libX11.so.6 => /lib/x86_64-linux-gnu/libX11.so.6 (0x00007febd8637000)
        libdl.so.2 => /lib/x86_64-linux-gnu/libdl.so.2 (0x00007febd8a3c000)
        libpthread.so.0 => /lib/x86_64-linux-gnu/libpthread.so.0 (0x00007febd8a37000)
        libstdc++.so.6 => /lib/x86_64-linux-gnu/libstdc++.so.6 (0x00007febd6e00000)
        libm.so.6 => /lib/x86_64-linux-gnu/libm.so.6 (0x00007febd7921000)
        libgcc_s.so.1 => /lib/x86_64-linux-gnu/libgcc_s.so.1 (0x00007febd8a17000)
        libc.so.6 => /lib/x86_64-linux-gnu/libc.so.6 (0x00007febd701f000)
        libxcb-cursor.so.0 => not found
        libglib-2.0.so.0 => /lib/x86_64-linux-gnu/libglib-2.0.so.0 (0x00007febd6cbd000)
        libgthread-2.0.so.0 => /lib/x86_64-linux-gnu/libgthread-2.0.so.0 (0x00007febd8a10000)
        libxcb-util.so.1 => /lib/x86_64-linux-gnu/libxcb-util.so.1 (0x00007febd8a08000)
        libXau.so.6 => /lib/x86_64-linux-gnu/libXau.so.6 (0x00007febd8a03000)
        libXdmcp.so.6 => /lib/x86_64-linux-gnu/libXdmcp.so.6 (0x00007febd6a00000)
        libEGL.so.1 => /lib/x86_64-linux-gnu/libEGL.so.1 (0x00007febd861f000)
        libfontconfig.so.1 => /lib/x86_64-linux-gnu/libfontconfig.so.1 (0x00007febd78d6000)
        libQt6DBus.so.6 => /home/user/.local/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/../../lib/libQt6DBus.so.6 (0x00007febd693b000)
        libz.so.1 => /lib/x86_64-linux-gnu/libz.so.1 (0x00007febd83e1000)
        libfreetype.so.6 => /lib/x86_64-linux-gnu/libfreetype.so.6 (0x00007febd6870000)
        libGLdispatch.so.0 => /lib/x86_64-linux-gnu/libGLdispatch.so.0 (0x00007febd67b7000)
        libGLX.so.0 => /lib/x86_64-linux-gnu/libGLX.so.0 (0x00007febd78a2000)
        libicui18n.so.56 => /home/user/.local/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/../../lib/libicui18n.so.56 (0x00007febd6200000)
        libicuuc.so.56 => /home/user/.local/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/../../lib/libicuuc.so.56 (0x00007febd5e00000)
        libicudata.so.56 => /home/user/.local/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/../../lib/libicudata.so.56 (0x00007febd4400000)
        librt.so.1 => /lib/x86_64-linux-gnu/librt.so.1 (0x00007febd8616000)
        /lib64/ld-linux-x86-64.so.2 (0x00007febd8ca7000)
        libpcre2-8.so.0 => /lib/x86_64-linux-gnu/libpcre2-8.so.0 (0x00007febd6c23000)
        libbsd.so.0 => /lib/x86_64-linux-gnu/libbsd.so.0 (0x00007febd83cb000)
        libexpat.so.1 => /lib/x86_64-linux-gnu/libexpat.so.1 (0x00007febd678c000)
        libdbus-1.so.3 => /lib/x86_64-linux-gnu/libdbus-1.so.3 (0x00007febd6736000)
        libpng16.so.16 => /lib/x86_64-linux-gnu/libpng16.so.16 (0x00007febd6700000)
        libbrotlidec.so.1 => /lib/x86_64-linux-gnu/libbrotlidec.so.1 (0x00007febd8607000)
        libmd.so.0 => /lib/x86_64-linux-gnu/libmd.so.0 (0x00007febd7895000)
        libsystemd.so.0 => /lib/x86_64-linux-gnu/libsystemd.so.0 (0x00007febd4331000)
        libbrotlicommon.so.1 => /lib/x86_64-linux-gnu/libbrotlicommon.so.1 (0x00007febd66dd000)
        libcap.so.2 => /lib/x86_64-linux-gnu/libcap.so.2 (0x00007febd6c17000)
        libgcrypt.so.20 => /lib/x86_64-linux-gnu/libgcrypt.so.20 (0x00007febd41ea000)
        liblzma.so.5 => /lib/x86_64-linux-gnu/liblzma.so.5 (0x00007febd66ae000)
        libzstd.so.1 => /lib/x86_64-linux-gnu/libzstd.so.1 (0x00007febd412e000)
        liblz4.so.1 => /lib/x86_64-linux-gnu/liblz4.so.1 (0x00007febd61da000)
        libgpg-error.so.0 => /lib/x86_64-linux-gnu/libgpg-error.so.0 (0x00007febd4106000)

As you can see the shared library which is not , appears like not found

    libxcb-cursor.so.0 => not found

Just thus easier to fix it , is using :

sudo apt install libxcb-cursor0

In your case could be another like: libxcb-randr0

IuriiV

@twar Hi, solved by sudo apt-get install libxcb*

fokhagyma

@IuriiV Thank you, it solved for me too.

booter

qt.qpa.plugin: Could not load the Qt platform plugin "xcb" in "" even though it was found.
This application failed to start because no Qt platform plugin could be initialized. Reinstalling the application may fix this problem.

Available platform plugins are: offscreen, wayland, vnc, minimalegl, xcb, wayland-egl, eglfs, linuxfb, vkkhrdisplay, minimal.

sudo apt-get install libxcb-randr0-dev libxcb-xtest0-dev libxcb-xinerama0-dev libxcb-shape0-dev libxcb-xkb-dev

sudo apt-get install libxkbcommon-x11-dev

sudo apt-get install libxcb-xinerama0

++++++++++++++++++++++++++++++++++

sudo apt-get install -qq libglu1-mesa-dev libx11-xcb-dev '^libxcb*'

jsulm

@booter As in your other thread: do you have a question? Please ask a clear question if you have one!
If you have same issue as in this thread then the solution should also be same: did you do that?

Spiv

@jsulm
Since I am getting the same error, I read the whole thread from the very beginning and tried all solutions but I still cannot load something....
I have Lenovo Ideapad Flex5 running Kubuntu.
I upgraded Kubuntu 20.04 first to 23.04,then to 23.10.
Then something happened ...
Now when I start the laptop I get to the login, put my password, the desktop and wallpaper show for 1 second, then I get a black screen.
Using Ctrl+Alt+F4 I can get to a terminal, but a cannot copy/paste anything into a browser since I cannot load a browser because I get an error very similar to the original post.
I am writing this through my phone.
I can take pictures of the terminal and the result of commands, but cannot paste anything....
Can you help me please regain my desktop display?

BTW, how do I attach pictures here?

SGaist

@Spiv hi and welcome to devnet,

Did you try to use the Wayland session rather than the Xorg ? You should be able to select that from the login screen.

Spiv

@SGaist
Hi, thank you for responding so quickly.
I don't know what you are suggesting, sorry....
How do I select a different (Wayland) session?

Spiv

I did figure that out...
With 'Plasma Wayland' I did not even see a flash of my desktop, just a dark screen.
'Plasma X11', desktop flash for a second, then black screen.
'Ubuntu' gave me a blue screen on which I can invoke all applications, including Firefox.
'Ubuntu Wayland' and 'Ubuntu on Xorg' also give me a working environment.
However, I cannot go into 'settings' for some reason.

SGaist

Did you check the logs of your system to see if something else is wrong ?

In any case, I would also check with the Kubuntu folks.

Octopic

@IuriiV mee too. If someone could add it in first comment it would be really helpful ;-)

mrt06

Hi, I am trying to run paraview for OpenFOAM but I have that error:


mrt06@DESKTOP-JQP308P:~$ paraview
qt.qpa.xcb: could not connect to display
qt.qpa.plugin: Could not load the Qt platform plugin "xcb" in "" even though it was found.
This application failed to start because no Qt platform plugin could be initialized. Reinstalling the application may fix this problem.

Available platform plugins are: eglfs, linuxfb, minimal, minimalegl, offscreen, vnc, xcb.

Aborted

Then I tried with QT_DEBUG_PLUGINS=1:

mrt06@DESKTOP-JQP308P:~$ export QT_DEBUG_PLUGINS=1
mrt06@DESKTOP-JQP308P:~$ paraview
QFactoryLoader::QFactoryLoader() checking directory path "/usr/lib/x86_64-linux-gnu/qt5/plugins/platforms" ...
QFactoryLoader::QFactoryLoader() looking at "/usr/lib/x86_64-linux-gnu/qt5/plugins/platforms/libqeglfs.so"
Found metadata in lib /usr/lib/x86_64-linux-gnu/qt5/plugins/platforms/libqeglfs.so, metadata=
{
    "IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3",
    "MetaData": {
        "Keys": [
            "eglfs"
        ]
    },
    "archreq": 0,
    "className": "QEglFSIntegrationPlugin",
    "debug": false,
    "version": 331520
}


Got keys from plugin meta data ("eglfs")
QFactoryLoader::QFactoryLoader() looking at "/usr/lib/x86_64-linux-gnu/qt5/plugins/platforms/libqlinuxfb.so"
Found metadata in lib /usr/lib/x86_64-linux-gnu/qt5/plugins/platforms/libqlinuxfb.so, metadata=
{
    "IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3",
    "MetaData": {
        "Keys": [
            "linuxfb"
        ]
    },
    "archreq": 0,
    "className": "QLinuxFbIntegrationPlugin",
    "debug": false,
    "version": 331520
}


Got keys from plugin meta data ("linuxfb")
QFactoryLoader::QFactoryLoader() looking at "/usr/lib/x86_64-linux-gnu/qt5/plugins/platforms/libqminimal.so"
Found metadata in lib /usr/lib/x86_64-linux-gnu/qt5/plugins/platforms/libqminimal.so, metadata=
{
    "IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3",
    "MetaData": {
        "Keys": [
            "minimal"
        ]
    },
    "archreq": 0,
    "className": "QMinimalIntegrationPlugin",
    "debug": false,
    "version": 331520
}


Got keys from plugin meta data ("minimal")
QFactoryLoader::QFactoryLoader() looking at "/usr/lib/x86_64-linux-gnu/qt5/plugins/platforms/libqminimalegl.so"
Found metadata in lib /usr/lib/x86_64-linux-gnu/qt5/plugins/platforms/libqminimalegl.so, metadata=
{
    "IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3",
    "MetaData": {
        "Keys": [
            "minimalegl"
        ]
    },
    "archreq": 0,
    "className": "QMinimalEglIntegrationPlugin",
    "debug": false,
    "version": 331520
}


Got keys from plugin meta data ("minimalegl")
QFactoryLoader::QFactoryLoader() looking at "/usr/lib/x86_64-linux-gnu/qt5/plugins/platforms/libqoffscreen.so"
Found metadata in lib /usr/lib/x86_64-linux-gnu/qt5/plugins/platforms/libqoffscreen.so, metadata=
{
    "IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3",
    "MetaData": {
        "Keys": [
            "offscreen"
        ]
    },
    "archreq": 0,
    "className": "QOffscreenIntegrationPlugin",
    "debug": false,
    "version": 331520
}


Got keys from plugin meta data ("offscreen")
QFactoryLoader::QFactoryLoader() looking at "/usr/lib/x86_64-linux-gnu/qt5/plugins/platforms/libqvnc.so"
Found metadata in lib /usr/lib/x86_64-linux-gnu/qt5/plugins/platforms/libqvnc.so, metadata=
{
    "IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3",
    "MetaData": {
        "Keys": [
            "vnc"
        ]
    },
    "archreq": 0,
    "className": "QVncIntegrationPlugin",
    "debug": false,
    "version": 331520
}


Got keys from plugin meta data ("vnc")
QFactoryLoader::QFactoryLoader() looking at "/usr/lib/x86_64-linux-gnu/qt5/plugins/platforms/libqxcb.so"
Found metadata in lib /usr/lib/x86_64-linux-gnu/qt5/plugins/platforms/libqxcb.so, metadata=
{
    "IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3",
    "MetaData": {
        "Keys": [
            "xcb"
        ]
    },
    "archreq": 0,
    "className": "QXcbIntegrationPlugin",
    "debug": false,
    "version": 331520
}


Got keys from plugin meta data ("xcb")
QFactoryLoader::QFactoryLoader() checking directory path "/usr/bin/platforms" ...
loaded library "/usr/lib/x86_64-linux-gnu/qt5/plugins/platforms/libqxcb.so"
qt.qpa.xcb: could not connect to display
qt.qpa.plugin: Could not load the Qt platform plugin "xcb" in "" even though it was found.
This application failed to start because no Qt platform plugin could be initialized. Reinstalling the application may fix this problem.

Available platform plugins are: eglfs, linuxfb, minimal, minimalegl, offscreen, vnc, xcb.

Aborted

After that I wrote that line without any conscious and get that:

mrt06@DESKTOP-JQP308P:~$ ldd /usr/lib/x86_64-linux-gnu/qt5/plugins/platforms/libqxcb.so
        linux-vdso.so.1 (0x00007fff2fbd8000)
        libQt5XcbQpa.so.5 => /lib/x86_64-linux-gnu/libQt5XcbQpa.so.5 (0x00007f10aff1b000)
        libQt5Gui.so.5 => /lib/x86_64-linux-gnu/libQt5Gui.so.5 (0x00007f10af83d000)
        libQt5Core.so.5 => /lib/x86_64-linux-gnu/libQt5Core.so.5 (0x00007f10af2de000)
        libstdc++.so.6 => /lib/x86_64-linux-gnu/libstdc++.so.6 (0x00007f10af0b2000)
        libc.so.6 => /lib/x86_64-linux-gnu/libc.so.6 (0x00007f10aee88000)
        libfontconfig.so.1 => /lib/x86_64-linux-gnu/libfontconfig.so.1 (0x00007f10aee3e000)
        libfreetype.so.6 => /lib/x86_64-linux-gnu/libfreetype.so.6 (0x00007f10aed76000)
        libQt5DBus.so.5 => /lib/x86_64-linux-gnu/libQt5DBus.so.5 (0x00007f10aece2000)
        libX11-xcb.so.1 => /lib/x86_64-linux-gnu/libX11-xcb.so.1 (0x00007f10aecdd000)
        libxcb-icccm.so.4 => /lib/x86_64-linux-gnu/libxcb-icccm.so.4 (0x00007f10aecd6000)
        libxcb-image.so.0 => /lib/x86_64-linux-gnu/libxcb-image.so.0 (0x00007f10aecce000)
        libxcb-shm.so.0 => /lib/x86_64-linux-gnu/libxcb-shm.so.0 (0x00007f10aecc9000)
        libxcb-keysyms.so.1 => /lib/x86_64-linux-gnu/libxcb-keysyms.so.1 (0x00007f10aecc4000)
        libxcb-randr.so.0 => /lib/x86_64-linux-gnu/libxcb-randr.so.0 (0x00007f10aecb1000)
        libxcb-render-util.so.0 => /lib/x86_64-linux-gnu/libxcb-render-util.so.0 (0x00007f10aecaa000)
        libxcb-render.so.0 => /lib/x86_64-linux-gnu/libxcb-render.so.0 (0x00007f10aec9b000)
        libxcb-shape.so.0 => /lib/x86_64-linux-gnu/libxcb-shape.so.0 (0x00007f10aec94000)
        libxcb-sync.so.1 => /lib/x86_64-linux-gnu/libxcb-sync.so.1 (0x00007f10aec8a000)
        libxcb-xfixes.so.0 => /lib/x86_64-linux-gnu/libxcb-xfixes.so.0 (0x00007f10aec80000)
        libxcb-xinerama.so.0 => /lib/x86_64-linux-gnu/libxcb-xinerama.so.0 (0x00007f10aec7b000)
        libxcb-xkb.so.1 => /lib/x86_64-linux-gnu/libxcb-xkb.so.1 (0x00007f10aec5d000)
        libxcb-xinput.so.0 => /lib/x86_64-linux-gnu/libxcb-xinput.so.0 (0x00007f10aec39000)
        libxcb.so.1 => /lib/x86_64-linux-gnu/libxcb.so.1 (0x00007f10aec0d000)
        libXrender.so.1 => /lib/x86_64-linux-gnu/libXrender.so.1 (0x00007f10aec00000)
        libX11.so.6 => /lib/x86_64-linux-gnu/libX11.so.6 (0x00007f10aeac0000)
        libSM.so.6 => /lib/x86_64-linux-gnu/libSM.so.6 (0x00007f10aeab5000)
        libICE.so.6 => /lib/x86_64-linux-gnu/libICE.so.6 (0x00007f10aea98000)
        libxkbcommon-x11.so.0 => /lib/x86_64-linux-gnu/libxkbcommon-x11.so.0 (0x00007f10aea8d000)
        libxkbcommon.so.0 => /lib/x86_64-linux-gnu/libxkbcommon.so.0 (0x00007f10aea44000)
        libglib-2.0.so.0 => /lib/x86_64-linux-gnu/libglib-2.0.so.0 (0x00007f10ae90a000)
        libm.so.6 => /lib/x86_64-linux-gnu/libm.so.6 (0x00007f10ae823000)
        libgcc_s.so.1 => /lib/x86_64-linux-gnu/libgcc_s.so.1 (0x00007f10ae803000)
        libGL.so.1 => /lib/x86_64-linux-gnu/libGL.so.1 (0x00007f10ae77c000)
        libpng16.so.16 => /lib/x86_64-linux-gnu/libpng16.so.16 (0x00007f10ae73f000)
        libz.so.1 => /lib/x86_64-linux-gnu/libz.so.1 (0x00007f10ae723000)
        libharfbuzz.so.0 => /lib/x86_64-linux-gnu/libharfbuzz.so.0 (0x00007f10ae654000)
        libmd4c.so.0 => /lib/x86_64-linux-gnu/libmd4c.so.0 (0x00007f10ae642000)
        libdouble-conversion.so.3 => /lib/x86_64-linux-gnu/libdouble-conversion.so.3 (0x00007f10ae62d000)
        libicui18n.so.70 => /lib/x86_64-linux-gnu/libicui18n.so.70 (0x00007f10ae2fe000)
        libicuuc.so.70 => /lib/x86_64-linux-gnu/libicuuc.so.70 (0x00007f10ae101000)
        libpcre2-16.so.0 => /lib/x86_64-linux-gnu/libpcre2-16.so.0 (0x00007f10ae077000)
        libzstd.so.1 => /lib/x86_64-linux-gnu/libzstd.so.1 (0x00007f10adfa8000)
        /lib64/ld-linux-x86-64.so.2 (0x00007f10b00b4000)
        libexpat.so.1 => /lib/x86_64-linux-gnu/libexpat.so.1 (0x00007f10adf77000)
        libuuid.so.1 => /lib/x86_64-linux-gnu/libuuid.so.1 (0x00007f10adf6e000)
        libbrotlidec.so.1 => /lib/x86_64-linux-gnu/libbrotlidec.so.1 (0x00007f10adf5e000)
        libdbus-1.so.3 => /lib/x86_64-linux-gnu/libdbus-1.so.3 (0x00007f10adf10000)
        libxcb-util.so.1 => /lib/x86_64-linux-gnu/libxcb-util.so.1 (0x00007f10adf07000)
        libXau.so.6 => /lib/x86_64-linux-gnu/libXau.so.6 (0x00007f10adf01000)
        libXdmcp.so.6 => /lib/x86_64-linux-gnu/libXdmcp.so.6 (0x00007f10adef9000)
        libbsd.so.0 => /lib/x86_64-linux-gnu/libbsd.so.0 (0x00007f10adedf000)
        libpcre.so.3 => /lib/x86_64-linux-gnu/libpcre.so.3 (0x00007f10ade69000)
        libGLdispatch.so.0 => /lib/x86_64-linux-gnu/libGLdispatch.so.0 (0x00007f10addb1000)
        libGLX.so.0 => /lib/x86_64-linux-gnu/libGLX.so.0 (0x00007f10add7d000)
        libgraphite2.so.3 => /lib/x86_64-linux-gnu/libgraphite2.so.3 (0x00007f10add56000)
        libicudata.so.70 => /lib/x86_64-linux-gnu/libicudata.so.70 (0x00007f10ac136000)
        libbrotlicommon.so.1 => /lib/x86_64-linux-gnu/libbrotlicommon.so.1 (0x00007f10ac113000)
        libsystemd.so.0 => /lib/x86_64-linux-gnu/libsystemd.so.0 (0x00007f10ac04c000)
        libmd.so.0 => /lib/x86_64-linux-gnu/libmd.so.0 (0x00007f10ac03f000)
        liblzma.so.5 => /lib/x86_64-linux-gnu/liblzma.so.5 (0x00007f10ac014000)
        liblz4.so.1 => /lib/x86_64-linux-gnu/liblz4.so.1 (0x00007f10abff2000)
        libcap.so.2 => /lib/x86_64-linux-gnu/libcap.so.2 (0x00007f10abfe7000)
        libgcrypt.so.20 => /lib/x86_64-linux-gnu/libgcrypt.so.20 (0x00007f10abea9000)
        libgpg-error.so.0 => /lib/x86_64-linux-gnu/libgpg-error.so.0 (0x00007f10abe83000)

I am using wsl2 Ubuntu and I have no idea with Linux. Can you please tell me what should I do? I tried to install libraries but nothing is changed

hskoglund

Hi, maybe your wsl2 needs an X Server to be running, or perhaps you have no vGPU driver installed. Or your Windows 10 is too old so you need to upgrade to Windows 11. More here

mrt06

This post is deleted!

Drexel

Had the same problem today. Activated QT_DEBUG_PLUGINS:

(.venv) raspifm@raspifm:~/Documents/src/raspiFM $  cd /home/raspifm/Documents/src/raspiFM ; /usr/bin/env /home/raspifm/Documents/src/raspiFM/.venv/bin/python /home/raspifm/.vscode/extensions/ms-python.python-2023.20.0/pythonFiles/lib/python/debugpy/adapter/../../debugpy/launcher 37365 -- -m src.touchui 
qt.core.plugin.factoryloader: checking directory path "/home/raspifm/Documents/src/raspiFM/.venv/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms" ...
qt.core.plugin.factoryloader: looking at "/home/raspifm/Documents/src/raspiFM/.venv/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqwayland-egl.so"
qt.core.plugin.loader: Found metadata in lib /home/raspifm/Documents/src/raspiFM/.venv/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqwayland-egl.so, metadata=
{
    "IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3",
    "MetaData": {
        "Keys": [
            "wayland-egl"
        ]
    },
    "archlevel": 0,
    "className": "QWaylandEglPlatformIntegrationPlugin",
    "debug": false,
    "version": 394752
}


qt.core.plugin.factoryloader: Got keys from plugin meta data QList("wayland-egl")
qt.core.plugin.factoryloader: looking at "/home/raspifm/Documents/src/raspiFM/.venv/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqoffscreen.so"
qt.core.plugin.loader: Found metadata in lib /home/raspifm/Documents/src/raspiFM/.venv/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqoffscreen.so, metadata=
{
    "IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3",
    "MetaData": {
        "Keys": [
            "offscreen"
        ]
    },
    "archlevel": 0,
    "className": "QOffscreenIntegrationPlugin",
    "debug": false,
    "version": 394752
}


qt.core.plugin.factoryloader: Got keys from plugin meta data QList("offscreen")
qt.core.plugin.factoryloader: looking at "/home/raspifm/Documents/src/raspiFM/.venv/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqlinuxfb.so"
qt.core.plugin.loader: Found metadata in lib /home/raspifm/Documents/src/raspiFM/.venv/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqlinuxfb.so, metadata=
{
    "IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3",
    "MetaData": {
        "Keys": [
            "linuxfb"
        ]
    },
    "archlevel": 0,
    "className": "QLinuxFbIntegrationPlugin",
    "debug": false,
    "version": 394752
}


qt.core.plugin.factoryloader: Got keys from plugin meta data QList("linuxfb")
qt.core.plugin.factoryloader: looking at "/home/raspifm/Documents/src/raspiFM/.venv/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqxcb.so"
qt.core.plugin.loader: Found metadata in lib /home/raspifm/Documents/src/raspiFM/.venv/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqxcb.so, metadata=
{
    "IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3",
    "MetaData": {
        "Keys": [
            "xcb"
        ]
    },
    "archlevel": 0,
    "className": "QXcbIntegrationPlugin",
    "debug": false,
    "version": 394752
}


qt.core.plugin.factoryloader: Got keys from plugin meta data QList("xcb")
qt.core.plugin.factoryloader: looking at "/home/raspifm/Documents/src/raspiFM/.venv/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqvnc.so"
qt.core.plugin.loader: Found metadata in lib /home/raspifm/Documents/src/raspiFM/.venv/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqvnc.so, metadata=
{
    "IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3",
    "MetaData": {
        "Keys": [
            "vnc"
        ]
    },
    "archlevel": 0,
    "className": "QVncIntegrationPlugin",
    "debug": false,
    "version": 394752
}


qt.core.plugin.factoryloader: Got keys from plugin meta data QList("vnc")
qt.core.plugin.factoryloader: looking at "/home/raspifm/Documents/src/raspiFM/.venv/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqminimalegl.so"
qt.core.plugin.loader: Found metadata in lib /home/raspifm/Documents/src/raspiFM/.venv/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqminimalegl.so, metadata=
{
    "IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3",
    "MetaData": {
        "Keys": [
            "minimalegl"
        ]
    },
    "archlevel": 0,
    "className": "QMinimalEglIntegrationPlugin",
    "debug": false,
    "version": 394752
}


qt.core.plugin.factoryloader: Got keys from plugin meta data QList("minimalegl")
qt.core.plugin.factoryloader: looking at "/home/raspifm/Documents/src/raspiFM/.venv/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqvkkhrdisplay.so"
qt.core.plugin.loader: Found metadata in lib /home/raspifm/Documents/src/raspiFM/.venv/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqvkkhrdisplay.so, metadata=
{
    "IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3",
    "MetaData": {
        "Keys": [
            "vkkhrdisplay"
        ]
    },
    "archlevel": 0,
    "className": "QVkKhrDisplayIntegrationPlugin",
    "debug": false,
    "version": 394752
}


qt.core.plugin.factoryloader: Got keys from plugin meta data QList("vkkhrdisplay")
qt.core.plugin.factoryloader: looking at "/home/raspifm/Documents/src/raspiFM/.venv/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqwayland-generic.so"
qt.core.plugin.loader: Found metadata in lib /home/raspifm/Documents/src/raspiFM/.venv/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqwayland-generic.so, metadata=
{
    "IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3",
    "MetaData": {
        "Keys": [
            "wayland"
        ]
    },
    "archlevel": 0,
    "className": "QWaylandIntegrationPlugin",
    "debug": false,
    "version": 394752
}


qt.core.plugin.factoryloader: Got keys from plugin meta data QList("wayland")
qt.core.plugin.factoryloader: looking at "/home/raspifm/Documents/src/raspiFM/.venv/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqeglfs.so"
qt.core.plugin.loader: Found metadata in lib /home/raspifm/Documents/src/raspiFM/.venv/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqeglfs.so, metadata=
{
    "IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3",
    "MetaData": {
        "Keys": [
            "eglfs"
        ]
    },
    "archlevel": 0,
    "className": "QEglFSIntegrationPlugin",
    "debug": false,
    "version": 394752
}


qt.core.plugin.factoryloader: Got keys from plugin meta data QList("eglfs")
qt.core.plugin.factoryloader: looking at "/home/raspifm/Documents/src/raspiFM/.venv/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqminimal.so"
qt.core.plugin.loader: Found metadata in lib /home/raspifm/Documents/src/raspiFM/.venv/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqminimal.so, metadata=
{
    "IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3",
    "MetaData": {
        "Keys": [
            "minimal"
        ]
    },
    "archlevel": 0,
    "className": "QMinimalIntegrationPlugin",
    "debug": false,
    "version": 394752
}


qt.core.plugin.factoryloader: Got keys from plugin meta data QList("minimal")
qt.core.plugin.factoryloader: checking directory path "/usr/bin/platforms" ...
qt.core.library: "/home/raspifm/Documents/src/raspiFM/.venv/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqxcb.so" cannot load: Cannot load library /home/raspifm/Documents/src/raspiFM/.venv/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqxcb.so: (libxcb-cursor.so.0: cannot open shared object file: No such file or directory)
qt.core.plugin.loader: QLibraryPrivate::loadPlugin failed on "/home/raspifm/Documents/src/raspiFM/.venv/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqxcb.so" : "Cannot load library /home/raspifm/Documents/src/raspiFM/.venv/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqxcb.so: (libxcb-cursor.so.0: cannot open shared object file: No such file or directory)"
qt.qpa.plugin: Could not load the Qt platform plugin "xcb" in "" even though it was found.
This application failed to start because no Qt platform plugin could be initialized. Reinstalling the application may fix this problem.

Available platform plugins are: wayland-egl, offscreen, linuxfb, xcb, vnc, minimalegl, vkkhrdisplay, wayland, eglfs, minimal.

Installed package libxcb-cursor0 and now it works....

mrt06

@hskoglund I updated my wsl and problem solved. thank you.

jonathan.taylor

I just spun up a fresh Ubuntu 23.10 box with default options selected. From there, I tried installing Qt first thing.

I couldn't launch the Qt Maintenance tool / installer until I did this:

sudo apt-get install -y build-essential libx11-xcb-dev libglu1-mesa-dev libxcb-xinerama0

After installation, I still couldn't launch Creator, running into error "qt.qpa.plugin: Could not load the Qt platform plugin "xcb" in "" even though it was found."

So, I found this web page (which appears to be for the benefit of Stamford students working on something or another I didn't bother trying to figure out) on how to install Qt on Linux: https://web.stanford.edu/dept/cs_edu/resources/qt/install-linux They aren't explicit about the Qt version the instructions at targeting, but there is a screenshot showing v6.5. I was aiming for v6.6.1 using Creator v12.0.1 and this worked for that as well.

That link says before doing anything (including running the installer) do this:

sudo apt-get update && sudo apt-get upgrade

That's obvious, of course, since it's the first step to most every such problem!

Then, they say do this:

sudo apt-get -y install build-essential openssl libssl-dev libssl1.0 libgl1-mesa-dev libqt5x11extras5 '^libxcb.*-dev' libx11-xcb-dev libglu1-mesa-dev libxrender-dev libxi-dev libxkbcommon-dev libxkbcommon-x11-dev

Once I ran that, the problem was resolved!

This is a shotgun approach, which I did rather blindly (as is common to do with cutting & pasting suggested solutions into Linux terminals when we just want to move forward without a deep dive!). I'm not sure that all of that is really needed (like qt 5 stuff?). It seems likely those are all the dependencies from whatever specifically those students needed for their project. If anyone wants to try this one-by-one and confirm the exact minimum requirements, that would be great! I figure I'll do that at some point, but not today...