JSFiddle - React, Tailwind, and code Playground

HTML

<label for="user_login">
    Username
    <br />
        <input id="user_login" class="input" type="text" size="20" value="" name="log" />
</label>

CSS

.hidden {
    display: none;
}

JavaScript

$(function() {
    var username_label = $('label[for="user_login"]');
    username_label.contents().eq(0).wrap('<span class="hidden"/>') // the text
    username_label.contents().eq(1).wrap('<span class="hidden"/>') // the <br />
});