[arch-general] LXQT: Unable to find an X11 visual which matches EGL config

[Zorro]

On 01/10/2018 07:44 AM, Gabriel E. wrote:
>> A question about Qt/LXQT.
>>
>> When starting LXQT with startlxqt LXQT crashes giving a core dump and
>> showing in the systemd logs the message
>> 'Unable to find an X11 visual which matches EGL config'
>>
>> The setup is connecting from a Windows 10 client to a system running 
>> Arch Linux using (x)rdp.
>>
>> On the Arch Linux system lxqt is started from ~/.xinitrc.
>> But a (x)rdp session is not created because of the above error.
>>
>> Changing 'exec startlxqt' into 'exec xterm' in ~/.xinitrc does indeed 
>> create a xrdp session but of course with just a xterm window.
>> Calling any Qt program in this terminal window leads to a core dump 
>> and that message
>> 'Unable to find an X11 visual which matches EGL config'
>> suggesting it's caused by Qt.
>>
>> Last weekend 6 Januari I did a pacman -Syu and Qt was updated to 
>> version 5.10.0.
>>
>> Does anybody have an idea what change in Qt may be causing this error ?
>>
>> Regards, Harm-Jan
>
> Qt (and also GTK) use OpenGL to render and EGL is part of OpenGL. 
> Xterm renders itself via Xlib, which doesn't need OpenGL. I would 
> suggest installing Mesa onto the Linux system, because Mesa is what 
> X11 uses for OpenGL. But I am not sure, it my also be possible to pipe 
> OpenGL over RDP.
>
I have Mesa installed on my Arch Linux system.

An interesting point you mention about piping OpenGL over RDP.

See the thing is that on my Arch Linux system I have also VNC (tigervnc 
1.7.1-1) running with LXQT as desktop environment and that goes well.

Also when I connect from my Windows Vista Desktop computer using RDP to 
my Arch Linux system LXQT also runs fine.
With the Windows 10 laptop I experience this error.

Maybe ask the people at xrdp if they have an idea.

Regards, Harm-Jan