How to show hidden elements in Javascript HTML
<p>I have hidden my div's with hidden="true" which is working but
I want to show it after a button click. </p>

<p>I work with Node.js and this part must be coded in Javascript.</p>

<p>html:</p>

<pre><code>div class="sideDiv" hidden="true"&gt;
</code></pre>

<p>javascript:</p>

<p>I tried it with show() but it doesn't work. </p>

<pre><code>socket.on('loginInServer',function(data){
        $('.sideDiv').show();
    });
</code></pre>