<p dir="auto">0.18.2 on windows , when close the devtools windows the renderer process not real closed. so repeatedly open and close the devtools cause multiple renderer processes remained.</p>
<p dir="auto">Here is my programme:</p>
<div class="highlight highlight-source-js notranslate position-relative overflow-auto" dir="auto" data-snippet-clipboard-copy-content="var app = require('app');  // Module to control application life.

// quit when all windows are closed.
app.on('window-all-closed', function() {
    app.quit();
});

app.on('ready', function() {
    var mainWindow = new BrowserWindow( { 
        title: &quot;foobar&quot;,
        width: 800, 
        height: 600,
        show: false,
        resizable: true,
    } );

    mainWindow.loadUrl('file://' + __dirname + '/index.html');
    mainWindow.show();
    // mainWindow.openDevTools();
});"><pre class="notranslate"><span class="pl-k">var</span> <span class="pl-s1">app</span> <span class="pl-c1">=</span> <span class="pl-en">require</span><span class="pl-kos">(</span><span class="pl-s">'app'</span><span class="pl-kos">)</span><span class="pl-kos">;</span>  <span class="pl-c">// Module to control application life.</span>

<span class="pl-c">// quit when all windows are closed.</span>
<span class="pl-s1">app</span><span class="pl-kos">.</span><span class="pl-en">on</span><span class="pl-kos">(</span><span class="pl-s">'window-all-closed'</span><span class="pl-kos">,</span> <span class="pl-k">function</span><span class="pl-kos">(</span><span class="pl-kos">)</span> <span class="pl-kos">{</span>
    <span class="pl-s1">app</span><span class="pl-kos">.</span><span class="pl-en">quit</span><span class="pl-kos">(</span><span class="pl-kos">)</span><span class="pl-kos">;</span>
<span class="pl-kos">}</span><span class="pl-kos">)</span><span class="pl-kos">;</span>

<span class="pl-s1">app</span><span class="pl-kos">.</span><span class="pl-en">on</span><span class="pl-kos">(</span><span class="pl-s">'ready'</span><span class="pl-kos">,</span> <span class="pl-k">function</span><span class="pl-kos">(</span><span class="pl-kos">)</span> <span class="pl-kos">{</span>
    <span class="pl-k">var</span> <span class="pl-s1">mainWindow</span> <span class="pl-c1">=</span> <span class="pl-k">new</span> <span class="pl-v">BrowserWindow</span><span class="pl-kos">(</span> <span class="pl-kos">{</span> 
        <span class="pl-c1">title</span>: <span class="pl-s">"foobar"</span><span class="pl-kos">,</span>
        <span class="pl-c1">width</span>: <span class="pl-c1">800</span><span class="pl-kos">,</span> 
        <span class="pl-c1">height</span>: <span class="pl-c1">600</span><span class="pl-kos">,</span>
        <span class="pl-c1">show</span>: <span class="pl-c1">false</span><span class="pl-kos">,</span>
        <span class="pl-c1">resizable</span>: <span class="pl-c1">true</span><span class="pl-kos">,</span>
    <span class="pl-kos">}</span> <span class="pl-kos">)</span><span class="pl-kos">;</span>

    <span class="pl-s1">mainWindow</span><span class="pl-kos">.</span><span class="pl-en">loadUrl</span><span class="pl-kos">(</span><span class="pl-s">'file://'</span> <span class="pl-c1">+</span> <span class="pl-s1">__dirname</span> <span class="pl-c1">+</span> <span class="pl-s">'/index.html'</span><span class="pl-kos">)</span><span class="pl-kos">;</span>
    <span class="pl-s1">mainWindow</span><span class="pl-kos">.</span><span class="pl-en">show</span><span class="pl-kos">(</span><span class="pl-kos">)</span><span class="pl-kos">;</span>
    <span class="pl-c">// mainWindow.openDevTools();</span>
<span class="pl-kos">}</span><span class="pl-kos">)</span><span class="pl-kos">;</span></pre></div>
<p dir="auto">If I comment out the <code class="notranslate">opendDevTools()</code> code, or if I open a dev-tools during using of my application, the application will not quit normally. It will stun at the end.</p>
<p dir="auto">I test this in atom-shell v18.2 in Mac OSX.</p>