title: PHP issue. Output stops sometimes after a specific echo
body: <p>I have got an issue that I don't know how to debug. Sometimes the output suddenly stops halfway through a PHP script, after a specific echo.</p>
  
  <p>This is a part of the code. After <code>someLonJsonString</code> the output sometimes stops. When the output stops, refreshing the page won't help, so it has something to do with the value also?</p>
  
  <pre><code>&lt;div class="ac-calendar-options"&gt;
      &lt;div class="timestamp"&gt;&lt;?php echo $currentTimestamp;?&gt;&lt;/div&gt; 
      &lt;div class="someLongJsonString"&gt;&lt;?php echo $someLongJsonString;?&gt;&lt;/div&gt;
      &lt;!-- The output of the script will cut off here --&gt;
      &lt;div class="timezone"&gt;&lt;?php echo $timezone;?&gt;&lt;/div&gt;
  &lt;/div&gt;
  </code></pre>
  
  <p>Refreshing won't help, but adding some useless echo before the long Json string does help: </p>
  
  <pre><code>&lt;div class="ac-calendar-options"&gt;
      &lt;div class="timestamp"&gt;&lt;?php echo $currentTimestamp;?&gt;&lt;/div&gt; 
      &lt;div style="display:none"&gt;&lt;?php echo "test"; ?&gt;&lt;/div&gt;
      &lt;div class="someLongJsonString"&gt;&lt;?php echo $someLongJsonString;?&gt;&lt;/div&gt;
      &lt;div class="timezone"&gt;&lt;?php echo $timezone;?&gt;&lt;/div&gt;
  &lt;/div&gt;
  </code></pre>
  
  <p>When I remove the <code>fix</code>, the problem comes back. Above <code>fix</code> does fix it for that item, but after a while, it pops up again but for another item with another JSON string.</p>
  
  <p>How can I debug this problem? Even temporarily showing the errors for that page/item does fix the problem. And I just don't understand why a simple echo will temporarily fix the problem.</p>
  
  <hr>
  
  <p>Since we moved to php 7.x from 5.6 this problem magically solved. </p>