I'm in need of some help to get my code completed. comment on pinterest, it's pretty simple

click in the comment box, write a message and click done.

the example url is this https://br.pinterest.com/pin/596445544385480354/

function sleep(ms){ 
    return(new Promise(function(resolve, reject) {
        setTimeout(function() { resolve(); }, ms);
    }));
}

(async function main(){
    
    var textarea = document.querySelector("#canonical-card > div:nth-child(3) > div > div.Jea.Tte.zI7.iyn.Hsu > div > div > div > div > div.Jea.LJB.Pw5.daS.fZz.gjz.qDf.rDA.zI7.iyn.Hsu > textarea");       
    textarea.dispatchEvent(new MouseEvent('click', {
      bubbles: true, cancelable: true
    }));

    await sleep(100);

    textarea = document.querySelector("#canonical-card > div:nth-child(3) > div > div.Jea.Tte.zI7.iyn.Hsu > div > div > div > div.hs0.un8.C9i > div.LJB.Pw5.Zr3.daS.hUC.ho-.ujU.zI7.iyn.Hsu > div > div > div.DraftEditor-editorContainer > div > div > div > div");
    textarea.innerText = "my Comment";
    
    textarea.dispatchEvent(new KeyboardEvent('keydown', {
      bubbles: true, cancelable: true, keyCode: 13
    }));
    
    var btnDone = document.querySelector("#canonical-card > div:nth-child(3) > div > div.Jea.Tte.zI7.iyn.Hsu > div > div > div > div.Jea.KO4.jx-.zI7.iyn.Hsu > div.JME.zI7.iyn.Hsu > div > button > div");
    btnDone.click();
    
})();

why does this code not work?