how can get the first div data with regex

I am trying to get the first div data through regex replace but i don’t know how can i do that because first time i am doing this. I am trying to get the data from mail

JS

previousValueDisplay() {
   return this.previousValue
        .replace()
}

<div dir="ltr">First div </div>
first div

i want to get the whole text from the first div like this

<div dir="ltr">First div <div>is use </div><div>for test</div></div>
First div is use for test