Having navigated to /admin/config/people/settings|Contact Settings
I have unchecked "Enable the personal contact form by default for new users."
Nonetheless, when I create a new user via the (annonymous) user registration form, then go to his own account, then click the "Edit" tab...
The Contact Settings tab still shows up, offering him the selection box,
" Personal contact form
Allow other users to contact you via a personal contact form which keeps your e-mail address hidden. Note that some privileged users such as site administrators are still able to contact you even if you choose to disable this feature."
It seems to me that this option should not show up.
I've cleared every cache I know how to clear. Is this an anomoly on my part, or a bug, or a feature?
It's a feature? ;-)
If you read the setting closely it says "Enable the personal contact form by default for new users." If you disable this, contact forms are still available for users, they are just NOT turned on by default.
The contact module has permissions and you can disable the ability for regular users to use personal contact forms, but you can't disable their ability to turn on their own own contact form.
This means you have a potential situation, in fact the default situation, where users are able to enable their personal contact form, but no one other than admins can use it, and admins could use it anyway according to the help text. This is weird.
I think that there should be a permission that grants (or removes) permission for users to enable their contact form. I'll create a github issue for this.