Mouse move and touch update events are not delivered correctly when there are modal dialogs

The problem has been confirmed on Linux and Windows. I haven't checked macOS yet but probably it is the same behavior. The attached reproducer includes a Rectangle and an InputPanel along with a Button which shows a modal Dialog by clicking. The modal Dialog is going to open another modal Dialog by clicking the Button in it. The behavior is different for Rectangle and InputPanel. Both of them are basically Item so I put them in the same bug report. But if they need to be separated, I can do that.

Build it against 6.8.2 and run it as it is (the Rectangle part)
1. The Rectangle can be dragged and pinched with both touching and mouse. This is the expected behavior.
2. Click the button to show a modal Dialog. Now, touching is not working whatsoever - neither dragging nor pinching is doable. Mouse is partially broken - dragging is not possible although pinching is still working.
3. Click the button in the modal dialog to open another modal dialog. This actually does not make any difference when it is a Rectangle being operated on.

And the InputPanel part (comment out line 76~100 and uncomment 52~74):
1. #Step 1 is no difference.
2. For #Step 2, touching actually works perfectly. Both dragging and pinching are doable. But still, dragging behaves the same for InputPanel (dragging fails but pinching is still OK).
3. #Step 3 is no difference (which essentially worsen the situation for InputPanel).

I will say that this bug report may be a follow-up of:
https://bugreports.qt.io/browse/QTBUG-130331
where press and release events are fixed. But according to my event filtered installed onto QGuiApplication itself, mouse move and touch update (maybe some other events too) are blocked, which causes the problem. But it feels little weird that InputPanel behaves differently from Rectangle, considering both are Item (maybe https://codereview.qt-project.org/c/qt/qtdeclarative/+/594839 does something unexpected).