How can a div at the top of the page coexist with Adminstration Menu?
One way of doing that with the CSS is as below:

.dev-query {
    position: fixed;
    top: 33px;
    width: 100%;
    left: 30px;
    color: #000;
    z-index: 100;
}


I have tried that and it seems to be working for me.



Another way of doing this with the JS I have mentioned here is somewhat like below:

&lt;div id="page-execution-time-custom"&gt;&lt;/div&gt;
&lt;script&gt;
(function ($) {
  // Jquery onload function.
  $(document).ready(function(){
    // Display the page execution time in the custom wrapper as below.
    var page_execution_time = $('.dev-query').text();
    $('#page-execution-time-custom').text(page_execution_time);
  });
})(jQuery); 
&lt;/script&gt;