How can I bypass the Ubuntu install username requirements?

While installing Ubuntu 21.04 for the first time, it asked me to pick a username. It wouldn't let me start my username with a capital letter. Is it possible to bypass this restriction during install?

A few workarounds I've tried:

• Using sudo adduser Testname --force-badname (This method worked, but it still prompted me for a username during install.)
• Editing NAME_REGEX in /etc/adduser.conf to allow for capitals.

Solution 1:

Is it possible to bypass this restriction during install?

No, you can not bypass this from a regular installation.

Using a capital in user names is bad though. It will break compliance with Windows in general and specific Linux software: "Username" and "username" are the same in Windows and also treated the same in Mail, FTP, LDAP, Active Director (and no it is not limited to this).

Using a full name in capitals will enable case folding. You would need to escape every capital letter wherever you use a capital. That will break your system.

To do this you would need to recreate a new Live session yourself and recompile for adduser to accept --force-badname as an option when creating a user. It is not only bad to do this but also a waste of time as you can easily do this AFTER installation with the command you already know sudo adduser Testname --force-badname.