shaarli-plugin-clickat/clickat.php

<?php
/**
 * ClickAt
 *
 * This plugin makes Twitter and Fediverse addresses clickable.
 */

use Shaarli\Config\ConfigManager;
use Shaarli\Plugin\PluginManager;
use Shaarli\Render\TemplatePage;

function hook_clickat_render_linklist($data)
{
   
    foreach ($data['links'] as &$value) {
        $value['description'] = preg_replace('/\ @([\w\d]+)@([\w\d_\-\.]+)/',' <a href="https://\2/@\1">&commat;\1</a>',$value['description']);
        $value['description'] = preg_replace('/\ @([\w\d]+)/',' <a href="https://twitter.com/\1">&commat;\1</a>',$value['description']);
    }
    return $data;
}