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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 - Scrolling is offset after touch event timeout"
   href="https://bugs.webkit.org/show_bug.cgi?id=144688">144688</a>
          </td>
        </tr>

        <tr>
          <th>Summary</th>
          <td>Scrolling is offset after touch event timeout
          </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>iOS
          </td>
        </tr>

        <tr>
          <th>OS</th>
          <td>iOS 8.2
          </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>Event Handling
          </td>
        </tr>

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

        <tr>
          <th>Reporter</th>
          <td>rbyers&#64;chromium.org
          </td>
        </tr></table>
      <p>
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        <pre>Repro on mobile Safari in iOS 8.3:
- Load <a href="http://rbyers.net/touch-timeout.html">http://rbyers.net/touch-timeout.html</a>
- Set the delay to 800ms
- Try scrolling anywhere within the blue border box
- After a brief delay, the document scrolls up
- Scroll it back down
- Now just touch (without scrolling) within the blue border box
- The moment your finger goes down, the page moves up.  WTF?

Note that the behavior is quite dynamic.  If you try with the default 300ms timeout first, then the behavior will not reproduce after increasing the timeout to 800ms (you must reload the page to see the issue).

I'm trying to better understand how scrolling in Safari reacts to slow touch event handlers and I'm very confused (some notes here: <a href="https://docs.google.com/document/d/12k_LL_Ot9GjF8zGWP9eI_3IMbSizD72susba0frg44Y/edit#heading=h.5zfdv2co2oj">https://docs.google.com/document/d/12k_LL_Ot9GjF8zGWP9eI_3IMbSizD72susba0frg44Y/edit#heading=h.5zfdv2co2oj</a>).  Is the code for this public or internal?</pre>
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