Ubuntu 20.04 needs `libxcb-xinerama.so.0`
and Debian 10 needs `libxcb-util.so.1` for the Qt `xcb` plugin.
-----
ported from 380f04a805
see https://github.com/Electron-Cash/Electron-Cash/issues/2196
-----
In particular, see this comment:
>> I confirmed that both Ubuntu 20.04 and Debian 10.8 clean install have an issue with the 4.2.4 AppImage.
>
> Any idea what broke it? I assume it used to work.
Yes, it did work in 4.2.3 which used PyQt5 5.13.2. I just had a look at the xcb plugin and it definitely has less dependencies:
```
ago@ubuntu2004vm:~/src/Electron-Cash/dist$ ldd squashfs-root/usr/lib/python3.6/site-packages/PyQt5/Qt/plugins/platforms/libqxcb.so|grep xcb
libX11-xcb.so.1 => /lib/x86_64-linux-gnu/libX11-xcb.so.1 (0x00007f0ec9d07000)
libxcb.so.1 => /lib/x86_64-linux-gnu/libxcb.so.1 (0x00007f0ec9cdd000)
libxcb-xkb.so.1 => /lib/x86_64-linux-gnu/libxcb-xkb.so.1 (0x00007f0ec6ead000)
```
compared to PyQt5 5.15.2 in 4.2.4:
```
ago@ubuntu2004vm:~/src/Electron-Cash/dist$ ldd squashfs-root/usr/lib/python3.8/site-packages/PyQt5/Qt/plugins/platforms/libqxcb.so|grep xcb
libX11-xcb.so.1 => /lib/x86_64-linux-gnu/libX11-xcb.so.1 (0x00007fcb5715f000)
libxcb-icccm.so.4 => /lib/x86_64-linux-gnu/libxcb-icccm.so.4 (0x00007fcb57158000)
libxcb-image.so.0 => /lib/x86_64-linux-gnu/libxcb-image.so.0 (0x00007fcb56f51000)
libxcb-shm.so.0 => /lib/x86_64-linux-gnu/libxcb-shm.so.0 (0x00007fcb56f4c000)
libxcb-util.so.1 => /lib/x86_64-linux-gnu/libxcb-util.so.1 (0x00007fcb56d46000)
libxcb-keysyms.so.1 => /lib/x86_64-linux-gnu/libxcb-keysyms.so.1 (0x00007fcb56d41000)
libxcb-randr.so.0 => /lib/x86_64-linux-gnu/libxcb-randr.so.0 (0x00007fcb56d2e000)
libxcb-render-util.so.0 => /lib/x86_64-linux-gnu/libxcb-render-util.so.0 (0x00007fcb56d27000)
libxcb-render.so.0 => /lib/x86_64-linux-gnu/libxcb-render.so.0 (0x00007fcb56d16000)
libxcb-shape.so.0 => /lib/x86_64-linux-gnu/libxcb-shape.so.0 (0x00007fcb56d11000)
libxcb-sync.so.1 => /lib/x86_64-linux-gnu/libxcb-sync.so.1 (0x00007fcb56d07000)
libxcb-xfixes.so.0 => /lib/x86_64-linux-gnu/libxcb-xfixes.so.0 (0x00007fcb56cfd000)
libxcb-xinerama.so.0 => /lib/x86_64-linux-gnu/libxcb-xinerama.so.0 (0x00007fcb56cf8000)
libxcb-xkb.so.1 => /lib/x86_64-linux-gnu/libxcb-xkb.so.1 (0x00007fcb56cda000)
libxcb.so.1 => /lib/x86_64-linux-gnu/libxcb.so.1 (0x00007fcb56cae000)
```
6e1caf7e88