The resize cursor is not show correctly when hovering over the splitter between the docked QDockWidgets.
This is problem is seen in Windows, and is not prominent on Mac.

When first resizing a vertical splitter and then hovering over a horizontal splitter the mouse cursor is showing the mouse cursor indicating vertical resizing when it should be the horizontal. What mouse cursor is set seems a bit arbitrary and sometimes it does not show a resize cursor at all.

It is not possible to see the the resize cursor until the actual resizing
of the docked qdockwidget has started. And when the resizing is finished
the cursor stays the resize cursor instead of reverting back to the arrow cursor.

Reproducible with demos/mainwindow, and calling in the constructor in mainwindow.cpp:
setAttribute(Qt::WA_Hover,false);