password_length' is not a supported key

Hi @szt,
I am unable to reproduce the error.
Steps followed:
1. Installed, enabled the module.
2. Updated the minimum password length to 5 characters from the admin/config/people/accounts page.
3. Tried creating a new account.
4. Worked as designated.

Attaching screenshot for the same.

Please let me know if there is any other configuration step that I'm missing.

Unfortunately I cannot reproduce it either :(
But the problem exists in my site.
Maybe the related issues give guide to you.
I am trying to find out how to reproduce it...

Hi @szt,
I was able to reproduce the issue.
Adding the steps for the same:
1. Install, enable the module.
2. Go to admin/config/people/accounts page.
3. Check/Enable the Require email verification when a visitor creates an account option.
4. Update the Minimum password length field as required.
5. Save the configuration, it gives an error: password_length' is not a supported key
Attached is the screenshot for the same.

Moving to NW.

The error is occurring due to the reason that when the verify email field is enabled, the user_admin_settings form validate() throws an exception that 'password_length' is an invalid key.

Used approach
Create a separate config file for storing the password length field value and retrieve it from the same, instead of updating the user schema.
Create a hook_update() to move the password length field value from the user schema to the config file for existing sites.

@szt please review

Works! Thanks!