Adding to flash message on new user save

I’m trying to figure out a way to let admins easily copy the activation link (i.e. UsersActivations->url) after they add new users. Ideally, this would look something like the screenshot below.

This way, the admin can send a personal email, which is less likely to end up in a junk folder. I like the idea of adding it to the flash message since it makes for a simple workflow, but I could also see adding this option for any existing users who have not been activated, as shown below.

Screenshot 2022-11-23 at 1.13.47 PM

So my question is whether filtering or appending to that flash message is supported or even possible to do cleanly using the API?

I think I could accomplish this in a messy way using the admin_users_browse hook, just looping through all the users and appending content using regex matching and some JavaScript. But that feels a little gross.

Does anyone have ideas for the best way to accomplish the general goal (if not the specifics)?

(PS: I would need to do this in a plugin; editing core is not helpful for my case)

A little progress, I found that I can add a message like so, but that it doesn’t accept HTML.

public function hookAdminUsersBrowse($args){
    if($somecondition = true){
        $message = __('lorem ipsum <a href="">this is not a link</a>');
        $flash = Zend_Controller_Action_HelperBroker::getStaticHelper('FlashMessenger');
        $flash->addMessage($message, 'success');

Also, as far as I can see, there’s no data available via $args that says which user was just added.

I would consider using $flash->getCurrentMessages() and/or $flash->hasMessages() but I’m not sure how to do so. Those seem to be returning an empty array or false, respectively, so I guess I’m doing something wrong.