How to set timeout for flash messages in Flash/Session

Try somethink like https://bootstrap-notify.remabledesigns.com/#demo

$("document").ready(function(){
    setTimeout(function(){
        $("div.alert").remove();
    }, 5000 ); // 5 secs

});

Not through js.....cant we set the session timeout in the function itself...like $this->session->delete

php outputs an html, after the html is send to the browser you see a "web page". After that the backend(php) cant control what your browser already have.

you can try using php sockets if you like https://socketo.me/docs/ but there is still some js ...