JSFiddle - React, Tailwind, and code Playground

HTML

<button id="mostrar" onClick="javascript: mostrarBt();">Mostrar Botão</button>
<button id="esconder" onClick="javascript: escondeBt();">Esconder Botão</button>
<button id="botao1">Botão 1</button>

CSS

button#botao1 {display: none; margin-top: 5px;}
#esconder{ display: none; margin-top: 5px; }

JavaScript

window.onload = function(){
	if(localStorage.mostrabotao2){
		mostrarBt();
	}
		
}

function mostrarBt() {
  document.getElementById("botao1").style.display="block";
  document.getElementById("esconder").style.display="block";
  localStorage.mostrabotao2 = 1;
}

function escondeBt() {
  document.getElementById("botao1").style.display="none";
  document.getElementById("esconder").style.display="none";
  localStorage.clear();
}