In qtvirtualkeyboard/qml-qtquick-virtualkeyboard-inputengine.html, a link is added to QVirtualKeyboardTrace:

-<a name="traceBegin-method"></a><span class="type">QVirtualKeyboardTrace</span> <span class="name">traceBegin</span>(<i>traceId</i>, <span class="type"><a href="../qtqml/qml-int.html">int</a></span> <i>patternRecognitionMode</i>, <span class="type"><a href="../qtqml/qml-var.html">var</a></span> <i>traceCaptureDeviceInfo</i>, <span class="type"><a href="../qtqml/qml-var.html">var</a></span> <i>traceScreenInfo</i>)</p></td></tr>
+<a name="traceBegin-method"></a><span class="type"><a href="qml-qvirtualkeyboardtrace.html">QVirtualKeyboardTrace</a></span> <span class="name">traceBegin</span>(<i>traceId</i>, <span class="type"><a href="../qtqml/qml-int.html">int</a></span> <i>patternRecognitionMode</i>, <span class="type"><a href="../qtqml/qml-var.html">var</a></span> <i>traceCaptureDeviceInfo</i>, <span class="type"><a href="../qtqml/qml-var.html">var</a></span> <i>traceScreenInfo</i>)</p></td></tr>

The file it links to, qml-qvirtualkeyboardtrace.html, doesn't exist. However, qvirtualkeyboardtrace.html does.