setCursor() stops working after interacting with a messagebox using the keyboard

Description:
After opening a QMessageBox and interacting with it using the keyboard (e.g., pressing Space or Enter to confirm), setCursor() no longer updates the cursor properly. The issue is inconsistent but occurs frequently.

Steps to Reproduce:

1. Run the provided minimal example.

1. Press Command + Drag to pan an image—this should correctly change the cursor to a hand icon.

1. Right-click to open a QMessageBox and interact with it using Space or Enter.

1. Try panning again—the cursor remains an arrow instead of changing to a hand.

Expected Behavior:
The cursor should update correctly after interacting with the QMessageBox, just as it does before opening it.

Actual Behavior:
After dismissing the QMessageBox with the keyboard, setCursor() no longer changes the cursor as expected.

Additional Information:

• A minimal example is attached.

• The [GitHub repository|https://github.com/eKevinHoang/QGraphicsBug] contains detailed steps and discussion.

• The issue was also discussed on the Qt Forum: [Qt Forum Thread|https://forum.qt.io/topic/161460/setcursor-stops-working-after-interacting-with-qmessagebox-using-space-key/11].