I have a page which has a iframe inside it, I want to execute some code when a DIV node is inserted in that iframe:

this code works inside firefox (version 82.0.2)

const innerObserver = new MutationObserver(function (mutations_list) {
    mutations_list.forEach(function (mutation) {
        mutation.addedNodes.forEach(function (node) {
            if (node.tagName == 'DIV' && node.className.indexOf('onlyoffice') >= 0) {
                console.log('[OnlyOffice Macro]: UI element insertion detected!')
                innerObserver.disconnect()
                node.setAttribute('id', uuid())
                const fileName = node.getAttribute('data-filename')
                listAttachments(node, `${fileName}.docx`)
            }
        })
    })
})

const outerObserver = new MutationObserver(function (mutations_list) {
    mutations_list.forEach(function (mutation) {
        mutation.addedNodes.forEach(function (node) {
            if (node.tagName == 'IFRAME' && node.className.indexOf('cke_wysiwyg_frame') >= 0) {
                outerObserver.disconnect()
                const iframe = node
                iframe.contentWindow.addEventListener('DOMContentLoaded', onCKEditorFrameLoaded, true)
                function onCKEditorFrameLoaded(ee) {
                    innerObserver.observe(iframe.contentWindow.document, { subtree: true, childList: true })
                }
            }
        })
    })
})

require(['jquery', 'bootstrap', 'http://172.25.161.211/web-apps/apps/api/documents/api.js'], function ($) {
    outerObserver.observe(document.querySelector('body'), { subtree: true, childList: true })
})

but not work in chrome(version 95.0.4638.69), even a div node with class 'onlyoffice' is already been rendered on screen, but chrome won't print anything on console.

do you have any idea what may cause the difference ?