QTreeWidget don't get focus when window get focus first time

Steps to reproduce:

-Create a minimal app with QTreeWidget and define this tree to be the widget getting focus when window get focus

Actual behavior:

-When opening window first time, screenreader (here NVDA) only announce window title but not tree, you have to switch to another window and than go back to app window, or open and close menu bar for tree to get focus

Expected behavior:

-Tree should get focus all time, even if window is open for the first time.

This should be reproduceable using this Qt example:

https://code.qt.io/cgit/qt/qtbase.git/tree/examples/widgets/itemviews/simpletreemodel?h=6.4