<html>
    <head>
      <base href="https://bugs.webkit.org/" />
    </head>
    <body><table border="1" cellspacing="0" cellpadding="8">
        <tr>
          <th>Bug ID</th>
          <td><a class="bz_bug_link 
          bz_status_NEW "
   title="NEW - No-op inline style changes cause style recalcs"
   href="https://bugs.webkit.org/show_bug.cgi?id=143327">143327</a>
          </td>
        </tr>

        <tr>
          <th>Summary</th>
          <td>No-op inline style changes cause style recalcs
          </td>
        </tr>

        <tr>
          <th>Classification</th>
          <td>Unclassified
          </td>
        </tr>

        <tr>
          <th>Product</th>
          <td>WebKit
          </td>
        </tr>

        <tr>
          <th>Version</th>
          <td>528+ (Nightly build)
          </td>
        </tr>

        <tr>
          <th>Hardware</th>
          <td>Unspecified
          </td>
        </tr>

        <tr>
          <th>OS</th>
          <td>Unspecified
          </td>
        </tr>

        <tr>
          <th>Status</th>
          <td>NEW
          </td>
        </tr>

        <tr>
          <th>Severity</th>
          <td>Normal
          </td>
        </tr>

        <tr>
          <th>Priority</th>
          <td>P2
          </td>
        </tr>

        <tr>
          <th>Component</th>
          <td>CSS
          </td>
        </tr>

        <tr>
          <th>Assignee</th>
          <td>webkit-unassigned&#64;lists.webkit.org
          </td>
        </tr>

        <tr>
          <th>Reporter</th>
          <td>esprehn&#64;chromium.org
          </td>
        </tr></table>
      <p>
        <div>
        <pre>Confirmed in r182227

&lt;div id=&quot;test&quot;&gt;&lt;/div&gt;
&lt;script&gt;
var test = document.getElementById(&quot;test&quot;);
setInterval(function() {
    test.style.top = &quot;0px&quot;;
});
&lt;/script&gt;

This causes an infinite number of style recalcs even though it's just assigning the same number repeatedly. It seems the parser returns true to mean &quot;successfully parsed&quot;, and the inline style machinery interprets that bool to mean &quot;something changed&quot;. Probably want to compare the CSSProperty objects to see that they're actually different instead (different value, different important).</pre>
        </div>
      </p>
      <hr>
      <span>You are receiving this mail because:</span>
      
      <ul>
          <li>You are the assignee for the bug.</li>
      </ul>
    </body>
</html>