replaceAll function is being marked as…?

The code you are seeing technically works. But VS Code, shows me an underline under the replaceAll function. I would like to know why, and what I could do to avoid this happening again.

renderTemplateText(str) {
    var parser = new DOMParser();
    var doc = parser.parseFromString(str, "text/html");
    var xRepeat = doc.querySelectorAll('[x-repeat]');
    var divarray = doc.querySelectorAll('[is^="x-"]');
    var divarraylength = divarray.length;


    for (var i = 0; i < divarraylength; i++) {                                                           
            var dataAttribute = divarray[i].getAttribute('data-link');                                                  
            console.log(divarray[i]);                                                    
            if (dataAttribute !== null) {                                           
                dataAttribute = dataAttribute.replaceAll("props", this.propsname);
            }                                                              
            console.log(dataAttribute );
    }
}

>Solution :

Youcan honestly just ignore this. Its just an "VS-Code thing".
I am assuming, it works? I made the not given value props myself, and it worked fine.