Is your feature request related to a problem? Please describe.
For a custom (self-hosted) server, only FQDNs are permitted as server URLs.
e.g. https://MyServer.domain.local
Bitwarden also permits https://MyServer.
Keyguard displays the message ‘Invalid URL’, but this is not correct. It is simply not an FQDN.

Describe the solution you'd like
Also do not accept FQDNs such as https://MyServer.

Describe alternatives you've considered

Additional context