### Tested versions

Godot Engine v4.2.stable.official.46dc27791

### System information

Windows 10

### Issue description

When exporting to web, Godot fails with this error in the console:

> scene/main/window.cpp:884 - Attempting to make child window exclusive, but the parent window already has another exclusive child. This window: /root/@<!-- -->EditorNode@<!-- -->17120/@<!-- -->Panel@<!-- -->13/@<!-- -->ProjectExportDialog@<!-- -->559/@<!-- -->VBoxContainer@<!-- -->137/@<!-- -->AcceptDialog@<!-- -->411, parent window: /root/@<!-- -->EditorNode@<!-- -->17120/@<!-- -->Panel@<!-- -->13/@<!-- -->ProjectExportDialog@<!-- -->559, current exclusive child window: /root/@<!-- -->EditorNode@<!-- -->17120/@<!-- -->Panel@<!-- -->13/@<!-- -->ProjectExportDialog@<!-- -->559/@<!-- -->ProgressDialog@<!-- -->17444

![a](https://github.com/godotengine/godot/assets/2000051/bf9d22aa-d3fe-4e11-bff6-c387e740fe90)

This happens for newly created empty projects.


### Steps to reproduce

1. Open the attached project (or create a new project).
2. Project->Export->Export All
3. Observe the console error.  No output files are generated.


### Minimal reproduction project (MRP)

[export_test.zip](https://github.com/godotengine/godot/files/13574810/export_test.zip)

static bool xcode_found = false;
	if (!xcode_found) {
		Vector<String> mdfind_paths;
		List<String> mdfind_args;
		mdfind_args.push_back("kMDItemCFBundleIdentifier=com.apple.dt.Xcode");
		String output;
		Error err = OS::get_singleton()->execute("mdfind", mdfind_args, &output);
		if (err == OK) {
			mdfind_paths = output.split("\n");
		}
		for (const String &found_path : mdfind_paths) {
			xcode_found = !found_path.is_empty() && DirAccess::dir_exists_absolute(found_path.strip_edges());
			if (xcode_found) {
				break;
			}
		}
	}
	return xcode_found;
}
void EditorExportPlatformIOS::_check_for_changes_poll_thread(void *ud) {