Error starting wireshark ubuntu 20.10

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Terminal output:

ubuntu@server:~$ wireshark
    qt.qpa.plugin: Could not find the Qt platform plugin "xcb" in ""
    This application failed to start because no Qt platform plugin could be initialized. Reinstalling the application may fix this problem.

Aborted (core dumped)

I Have a problem on one of my servers to start wireshark with a user "ubuntu " which is nnot a root user " I already add permission ect ... usermod -a -G wireshark/chmod 750 /usr/bin/dumpcap / setcap cap_net_raw,cap_net_admin=eip /usr/bin/dumpcap on this user. I also tried to install qt5... sudo apt-get install --reinstall qt5-default without success what could be the problem ?

Br,

boomy