Is your feature request related to a problem? Please describe.

I have allowed user registration on my site and the New User Account Activation option is set to Admin, so the user will be emailed a link to activate their account before they can log in. Then all users set to receive system emails and who have the permission to create users will be notified to activate the user's account.

This works as expected. However if the user clicks the activation link a second time the following message is displayed;

Error 403 - verification code not found

Describe the solution you'd like

It seems logical, and good UX, that rather than a 403 error (which normally means access is forbidden), there should be a custom message displayed to the user e.g.;

Sorry, there was a problem, we couldn't validate that code, it may be:

Already validated
Expired

Additional context

I'm aware that Joomla does not store the activation token once a user has been activated.

Other sites I've registered on have this functionality (e.g. MailChimp).