28. February 2024

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

After the installation of QtCreator on Linux you might get following error messag when launching the application:

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.

It is likely one of libraries required by xcb is missing.

To resolve this problem find libxcb.so and run ldd to identify the missing library.

find ~/Qt -name libqxcb.so -exec ldd {} \; | grep "not found"

Install the missing dependency. E.g.:

sudo apt-get install libxcb-cursor0

11. September 2017

How to increase font size in Wireshark 2.4 on Windows

Wireshark is based on the new version of QT, and it has a similar problem on Windows like pgAdmin 4.

If you have a screen with higher density, the font will be too small.

The solution is to add one parameter for QT engine to handle DPI differently.

Open PowerShell as Administrator and go to the directory with Wireshark open qt.conf file:

cd "C:\Program Files\Wireshark"
notepad qt.conf

Write there following content:

[Platforms]
WindowsArguments = dpiawareness=0

Save the file and start Wireshark.

Note: make sure that the file name is just qt.conf. Notepad could add .txt file extension when saving the file directly from Notepad.

Enjoy bigger font:

2. March 2017

How to increase font size in pgAdmin 4 on Windows

New version of pgAdmin 4 is based on QT5. When you install pgAdmin 4 on Windows computer with a high-density display you may see that letters are too small.

Solution is to send one parameter to QT engine. It will handle DPI in different way.

Open PowerShell and go to directory with pgAdmin. Then launch application with parameter:

cd "c:\Program Files\PostgreSQL\9.6\pgAdmin 4\bin"
.\pgAdmin4.exe -platform windows:dpiawareness=0

You can persist the configuration by creating qt.conf. Start PowerShell as Administrator.

Click Windows Start menu and type: powershell. Then right-click and select the option: Run as Administrator.

Go to directory with pgAdmin and create the file:

cd "c:\Program Files\PostgreSQL\9.6\pgAdmin 4\bin"
notepad qt.conf

Write there following content:

[Platforms]
WindowsArguments = dpiawareness=0

Save the file and start pgAdmin 4 and enjoy new font size.

Note: make sure that the file name is just qt.conf. Notepad could add .txt file extension when saving the file directly from Notepad.