JSFiddle - React, Tailwind, and code Playground

HTML

<link rel="stylesheet" href="http://wp-simplicity.com/wp-content/themes/simplicity-child-simplicity/style.css">
<div class="article">

        <h1 class="entry-title">投稿ページタイトルを 指定した場所で改行したい</h1>
        <p class="post-meta">
                    <span class="post-date"><span class="fa fa-clock-o fa-fw"></span><span class="entry-date date published"></span></span>
              <span class="post-update"><span class="fa fa-history fa-fw"></span><time class="entry-date date updated" datetime="">2015/11/25</time></span>
    
          
                  </p>

JavaScript

(function ($) {
	$(function(){
    	var title = $(".entry-title").text().replace(" ","<br>");
        $(".entry-title").html(title);
    });
})(jQuery);