Odoo creates a contact for each company in the system. I used this contact for one of companies in the system to give access to someone as Internal User, but now I don't see him on the users list with default filter enabled (I can see him on the list with all the users). Why is that?
I've checked that default filter uses field called "shared" inside res.users and requires it to be true. But what does it mean exactly. Why it is False for this automatically created contact? Is it safe to use it as a Internal User account?
You can not provide access using a contact, only using a user. Your post is very confusing to me, I don't understand your problem.
There is a functionality inside contact for giving access to a portal and then you can change user type from Portal to Internal.
What do you want to achieve, or why do you not want to create internal users the proper way?
Because existing contact already has a proper email and vat number assign and that my new user user should use. So instead of creating new one (and cause duplicate contact entries with vat number and email) I wanted to use this one.