The concern seems to be related to the Debian security policy regarding sandboxing. I found this thread that talks about it: https://github.com/tutao/tutanota/issues/1565.
There is a workaround which consists of adding the following command to the /etc/sysctl.conf file:
kernel.unprivileged_userns_clone = 1.
But it doesn’t seem great regarding the security of the kernel.
So I made a sudo chmod 4755 chrome-sandbox in /opt/Local
Everything works perfectly and Local is running properly now! 