I have the following Javascript/Jquery code:

       <script type="text/javascript">
            function ChangeMathOnPage() {
                MathJax.Hub.Queue(["Typeset",MathJax.Hub]);
            }

            $('.markdownx-preview').each(function(){
                $(this).on('DOMSubtreeModified', ChangeMathOnPage);
            });
        </script>

This does my job. However, as explained here, use of DOMSubtreeModified is deprecated.

To somebody new to Javascript/Jquery world, please explain ways to convert same logic into non-deprecated code.

I have the following Javascript/Jquery code:

       <script type="text/javascript">
            function ChangeMathOnPage() {
                MathJax.Hub.Queue(["Typeset",MathJax.Hub]);
            }

            $('.markdownx-preview').each(function(){
                $(this).on('DOMSubtreeModified', ChangeMathOnPage);
            });
        </script>

This does my job. However, as explained here, use of DOMSubtreeModified is deprecated.

To somebody new to Javascript/Jquery world, please explain ways to convert same logic into non-deprecated code.

• javascript
• jquery

• 2 try to follow the "Example usage" on MutationObserver, – DIEGO CARRASCAL Commented Apr 30, 2018 at 19:48
• 1 Look here... Probably relevant to you: stackoverflow./a/14570614/2159528 – Louys Patrice Bessette Commented Apr 30, 2018 at 20:16

1 Answer 1

Try this:

// Select the node that will be observed for mutations
var targetNode = document.getElementById('some-id');

// Options for the observer (which mutations to observe)
var config = { attributes: true, childList: true };

// Callback function to execute when mutations are observed
var callback = function(mutationsList) {
    for(var mutation of mutationsList) {
        if (mutation.type == 'childList') {
            console.log('A child node has been added or removed.');
        }
        else if (mutation.type == 'attributes') {
            console.log('The ' + mutation.attributeName + ' attribute was modified.');
        }
    }
};

// Create an observer instance linked to the callback function
var observer = new MutationObserver(callback);

// Start observing the target node for configured mutations
observer.observe(targetNode, config);

// Later, you can stop observing
observer.disconnect();

Source: MDN: MutationObserver