Error while loading shared libraries: libX11.so.6 [closed]

Question

I installed authy using the snap install authy command. When I try to open the application, I get the following error message: /snap/authy/6/authy: error loading shared libraries: libX11.so.6: unable to open shared objects file: No such file or directory

Ubuntu 20.04.3 LTS

Answer 1

Installing libx11-6:i386 worked for me:

sudo apt-get install libx11-6:i386

after that I experienced another error solved by installing libstdc++5:i386:

sudo apt-get install libstdc++5:i386

Answer 2

In my case a Citrix icaclient installation caused the issue.

Affected applications were Thunderbird and VLC

sudo dpkg --purge icaclient

fixed the issue, no reboot was required.