### 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)

if (updating) {
		return;
	}
	Ref<EditorExportPreset> current = get_current_preset();
	ERR_FAIL_COND(current.is_null());
	current->set_script_encryption_key(p_key);
	updating_script_key = true;
	_update_current_preset();
	updating_script_key = false;
}
bool ProjectExportDialog::_validate_script_encryption_key(const String &p_key) {
	bool is_valid = false;
	if (!p_key.is_empty() && p_key.is_valid_hex_number(false) && p_key.length() == 64) {
		is_valid = true;
	}
	return is_valid;
}
void ProjectExportDialog::_duplicate_preset() {
	Ref<EditorExportPreset> current = get_current_preset();
	if (current.is_null()) {
		return;
	}
	Ref<EditorExportPreset> preset = current->get_platform()->create_preset();
	ERR_FAIL_COND(!preset.is_valid());
	String preset_name = current->get_name() + " (copy)";
	bool make_runnable = true;
	while (true) {
		bool valid = true;
		for (int i = 0; i < EditorExport::get_singleton()->get_export_preset_count(); i++) {
			Ref<EditorExportPreset> p = EditorExport::get_singleton()->get_export_preset(i);