JSFiddle - React, Tailwind, and code Playground
HTML
<ul class="sub-menu">
<li id="menu-item-1" class="menu-item">
<a href="/page1">Page1</a>
</li>
<li id="menu-item-2" class="menu-item">
<a href="/page2"> </a>
</li>
<li id="menu-item-3" class="menu-item">
<a href="/page3">Page3</a>
</li>
</ul>
JavaScript
var link=document.getElementsByTagName("a");
for(var i=0;i<link.length;i++)
if(link[i].innerHTML.replace(/^\s+|\s+$/g, "")==='Page1')
link[i].parentNode.style.display="hidden";