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      <base href="https://bugs.webkit.org/" />
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    <body><table border="1" cellspacing="0" cellpadding="8">
        <tr>
          <th>Bug ID</th>
          <td><a class="bz_bug_link 
          bz_status_NEW "
   title="NEW - pseudo-element transitions on hover have a delay"
   href="https://bugs.webkit.org/show_bug.cgi?id=163078">163078</a>
          </td>
        </tr>

        <tr>
          <th>Summary</th>
          <td>pseudo-element transitions on hover have a delay
          </td>
        </tr>

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

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

        <tr>
          <th>Version</th>
          <td>WebKit Nightly Build
          </td>
        </tr>

        <tr>
          <th>Hardware</th>
          <td>PC
          </td>
        </tr>

        <tr>
          <th>OS</th>
          <td>Windows 7
          </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>hibbard.tyler&#64;gmail.com
          </td>
        </tr></table>
      <p>
        <div>
        <pre>When there are two :hover pseudo-classes at play--one for an element's :hover styles and another for a child element's pseudo-element hover styles (see example below)--the transition on the pseudo-element seems to have an erratic delay:

parent:hover {}
parent:hover child::after {}

Removing the initial parent:hover {} styles seem to rectify this issue and cause the pseudo-element's transition to run immediately as expected.

Here's a JSFiddle demo that runs transitions concurrently in Firefox, IE11, even Safari 5.1.7, but has a delay in Chrome:
<a href="https://jsfiddle.net/vzpbuk62/3/">https://jsfiddle.net/vzpbuk62/3/</a></pre>
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