use DOM MutationObserver!

mutationObserverForYTP.html

0.00MB

(function(){
const div=document.createElement("div");
div.setAttribute('id','transcript');
div.setAttribute('width',"100%");
div.setAttribute('height','200px');
div.setAttribute('style',"position:absolute;width:100%;background:skyblue;z-index:9999;text-align:center;font-size:38px;");
if(document.querySelector('#transcript')){document.querySelector('#transcript').remove();}
document.body.insertBefore(div,document.body.firstElementChild);
var observer=new MutationObserver(function(mutations){
//to do;
console.log(mutations);
mutations.forEach(function(mutation){

//if(mutation.type=='characterData'){console.log(mutation.target)};
if(mutation.type=='childList'){console.log(mutation.target.innerHTML);
div.innerHTML =mutation.target.innerHTML;

}

})
});

var target=document.querySelector("#ytp-caption-window-container");

var options={
childList:true,
subtree:true
}

observer.observe(target,options);

})()