Excuse me if my question is not well asked, I will explain the problem. I have an element <div class="o_notification_manager"></div> that appears after an uncertain time on the screen to display notifications. I want to make changes on this element as soon as it is displayed.

I thought of something like this with jquery

$(document.querySelector('.o_notification_manager')).ready(function() {
    console.log(document.querySelector('.o_notification_manager').innerHTML);
});

But I get this error

When I use the setTimeout() or setInterval() function, I get two error cases:

• Either my code runs before the element is displayed and I get the previous error;
• or my code runs after the element is displayed and the user sees the element change (he sees the content change, the width change). I want my code to run at the same time as the element is displayed. Any help is welcome.