Allow anonymous users to send email to a certain user in MediaWiki

I have a MediaWiki 1.33.0 website with only one user profile at the moment; this is my own user profile (Admin).
It seems to me that naturally, in MediaWiki, anonymous users cannot send email to a registered user through its user profile (yet this is possible for registered users (if that user permitted getting emails from other registered users).

My problem

I desire to allow anonymous users to send me an email through that user profile;
I went through the email preferences of Admin and found no way to do so - only registered users can send such email.
To illustrate, if I go to: https://example.com/index.php?title=user:Admin
The option that would available for any registered user "Send an email to that user" in sidebar, doesn't appear.

Potential solution

There are PHP extensions for MediaWiki that allow a contact form available for all users, like ContactPage but I desire an extensionless solution if there is one (the site doesn't have extensions and I'd prefer to keep it this way to reduce complexity).

My question

As a non PHP developer I ask; is there a PHP hook (or tweak?) usable in LocalSettings.php to allow anonymous users to send me email through that profile?
If not, is there a Wiki syntax API call or an AJAJ call to bypass the PHP restriction?