JSFiddle - React, Tailwind, and code Playground

HTML

<span class="externallink">
    <a href="http://www.google.com">Google.com</a> 
    <span class="externallink__ext">
        [<a href="http://www.google.com" target="_blank">open in new window/tab</a>]
    </span>
</span>

CSS

.externallink .externallink__ext {
    display: none;
}
.externallink:hover .externallink__ext {
    display: inline;
}