Unwanted highlight of arrows in tree view when hovering with mouse

The attached code is a slightly modified version of the editabletreemodel sample found in src/qtbase/examples/widgets/itemviews.
Modification done: A style sheet has been added to mainwindow.cpp.

Hovering over the arrow for expanding/collapsing elements in the tree view or the blank space if the tree item has been expanded causes the arrow or blank space to be highlighted when it shouldn't be, and that hightlighting doesn't always clear when it should.

If you try to build this sample code using Qt 5.15.12, everything works fine.

Steps to reproduce:
1) build and run the attached example with Qt 6.2.7 or higher version (6.5.1)
2) hover over the arrow for expanding/collapsing elements in the tree view or the blank space