Checklist

• I have searched for similar issues.
• For Python issues, I have tested with the latest development wheel.
• I have checked the release documentation and the latest documentation (for master branch).

Describe the issue

It seems that the Combobox widget freezes when changing selections under MacOS. This behaviour worked in version 0.14.0 and 0.15.0 but is broken since 0.16.1 (and 0.17.0).

After clicking on the element the loading cursor is shown and the window is unresponsive and has to be closed.

Steps to reproduce the bug

Either use the following script or just download the Open3D Viewer under MacOS and try to change a combobox item.

from open3d.cpu.pybind.visualization import gui

app = gui.Application.instance
app.initialize()

window: gui.Window = gui.Application.instance.create_window("Demo Window", 200, 400)
vert = gui.Vert()

box = gui.Combobox()
box.add_item("hello")
box.add_item("world")
box.add_item("now")

vert.add_child(box)

window.add_child(vert)

app.run()

Error message

No error message.

Expected behavior

The selected item is shown in the Combobox. No lags, no freezes.

Open3D, Python and System information

- Operating system: macOS 12.6 (M1)
- Python version: Python 3.9
- Open3D version: 0.17.0
- System architecture: apple-silicon
- Is this a remote workstation?: no
- How did you install Open3D?: pip

Additional information

No response