Issue: Adding new Quote/Invoice for non-existing Client

In the documentation Here it says:

When creating a quote, start typing the name of the client to create the quote for. If it's an existing client, choose their name from the list that appears. If it's a new client, type their full name or business name.

However in practice, when I try to add new quote for a non-existing client, it does not allow me to give the name and create the quote. I would have to create the client first in the other menu and then comeback to create the quote/invoice. I am using Version 1.5.3

Any help about fixing this issue/bug is appreciated.

Thanks.

It its not a bug, the documentation is outdated. Please create a client before you add any new quotes or invoices.

Thanks for the reply.
For my use-cases it happens a lot that I need to create a quick quote for non-existing clients.
As the only required field for client is ‘name’, which document or source file should I consult to implement the quick client add in the new quote/invoice page? Is there any ajax handler defined for creating new client in any controller?

Thanks.

Any suggestion?