Statistic: Make modal static to improve mobile UX

themes/xmpp-providers/layouts/shortcodes/statistics.html

@@ -122,7 +122,7 @@ <h3 id="provider-distribution">
     </div>
 </div>
 
-<div id="statistics_details_modal" class="modal" tabindex="-1">
+<div id="statistics_details_modal" class="modal fade" tabindex="-1" data-bs-backdrop="static">
     <div class="modal-dialog modal-dialog-centered modal-dialog-scrollable">
         <div class="modal-content">
             <div class="modal-header">