title: Unexpected Safari page load count behavior
body: <h2>Client</h2>
  
  <ul>
  <li>Mac OS 10.15.3</li>
  </ul>
  
  <h2>Server</h2>
  
  <ul>
  <li>Ubuntu 18.04.4</li>
  <li>Apache 2.4.29</li>
  <li>PHP 7.4.5</li>
  </ul>
  
  <p>Take a script, call it /test.php.  Let's track how many <em>actual</em> page loads happen per visual, user-experienced page load.</p>
  
  <pre><code># Count = 1
  test.php?v=1
  # Count = 2
  test.php?v=1
  # Count = 4 (???)
  test.php?v=2
  # Count = 7 (???)
  test.php?v=1
  # Count = 8 
  test.php?v=1
  # Count = 10 (???)
  test.php?v=3
  # Count = 11
  test.php?v=3
  # Count = 15 (???)
  test.php?v=2
  # Count = 18 (???)
  test.php?v=1
  </code></pre>
  
  <p>In Chrome, the number of loads is as expected - 1, 2, 3, then 4, 5, etc.  </p>
  
  <p>Furthermore, Safari behaves as expected - as Chrome behaves - if you do this in a Private Window.</p>
  
  <p>Why is Safari behaving like this?  Is there contribution from something else in the stack, such as from Apache or PHP?</p>
  
  <h2>EDIT 1</h2>
  
  <p>Apache log of a smaller test case.  <strong>(!!!)</strong> test.php?v=3 is logged despite not willfully being requested by me.</p>
  
  <pre><code># Procedure
  test.php?v=1
  test.php?v=1
  test.php?v=2
  </code></pre>
  
  <pre><code># Apache Log of above page loads with IP redacted.
  REDACTED_IP - - [20/Apr/2020:11:35:26 +0000] "GET /test.php?v=1 HTTP/1.1" 200 8875 "-" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_3) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/13.0.5 Safari/605.1.15"
  REDACTED_IP - - [20/Apr/2020:11:35:28 +0000] "GET /test.php?v=1 HTTP/1.1" 200 5141 "-" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_3) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/13.0.5 Safari/605.1.15"
  REDACTED_IP - - [20/Apr/2020:11:35:42 +0000] "GET /test.php?v=3 HTTP/1.1" 200 8876 "-" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_3) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/13.0.5 Safari/605.1.15"
  REDACTED_IP - - [20/Apr/2020:11:35:42 +0000] "GET /test.php?v=2 HTTP/1.1" 200 5141 "-" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_3) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/13.0.5 Safari/605.1.15"
  REDACTED_IP - - [20/Apr/2020:11:35:43 +0000] "GET /test.php?v=2 HTTP/1.1" 200 5705 "-" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_3) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/13.0.5 Safari/605.1.15"
  </code></pre>
  
  <h2>Edit 2</h2>
  
  <p>Here are the stripped-down contents of test.php.  Requires Redis and PHP-Redis, as I'm using that for a quick visual.  You can of course use Apache logs instead if you wish, or any other way to quickly see the number of times the script has been executed.</p>
  
  <pre><code>&lt;?php 
  $redis = new Redis();
  $redis-&gt;connect('127.0.0.1', 6379);
  
  echo $redis-&gt;incr('counter');
  </code></pre>