Qt creator crashes when operating "Shift + Alt" and mouse buttons

1. Load a project and open a file in the editor.
2. Press "Shift + Alt" and left mouse button, select a chunk of texts in the editor.
3. Release left mouse button.
4. Press left mouse button again on that chunk of texts.
5. Drag the mouse away, the mouse cursor will get an additional right arrow underneath.
6. Also press right mouse button.
7. Release right mouse button.
8. Release left mouse button.
9. Qt creator will crash.

"Shift + Alt" should keep being pressed.

It does not happen every time. I noticed this issue by accident.