I tried to install calibre in Ubuntu 20.04 and it won't launch.
I followed the instructions from another question (Calibre No Longer Working) but it didn't work.
This is how I installed (version 5.20.0):

sudo -v && wget -nv -O- https://download.calibre-ebook.com/linux-installer.sh | sudo sh /dev/stdin

I'm getting this error:

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, wayland-egl, wayland, wayland-xcomposite-egl, wayland-xcomposite-glx, xcb.



Aborted (core dumped)

Any ideas?