### Godot version

v4.2.beta2.official [f8818f85e]

### System information

Windows 10, 64bit

### Issue description

Some times can't add node in visualshader editor

### Steps to reproduce

1. Open a VisualShader file for edit.
2. Click the `Add Node...` button, it will popup menu, it is OK.
3. Direct close the menu.
4. Clikd the `Add Node...` again, the menu can't popup.
![GIF](https://github.com/godotengine/godot/assets/35988767/1326c63e-3e05-4423-9ec7-7ce305b3f4f5)

### Minimal reproduction project

/
_add_varying(varying_name->get_text(), (VisualShader::VaryingMode)varying_mode->get_selected(), (VisualShader::VaryingType)varying_type->get_selected());
	add_varying_dialog->hide();
}
void VisualShaderEditor::_varying_name_changed(const String &p_text) {
	String name = p_text;
	if (!name.is_valid_identifier()) {
		varying_error_label->show();
		varying_error_label->set_text(TTR("Invalid name for varying."));
		add_varying_dialog->get_ok_button()->set_disabled(true);
		return;
	}
	if (visual_shader->has_varying(name)) {
		varying_error_label->show();
		varying_error_label->set_text(TTR("Varying with that name is already exist."));
		add_varying_dialog->get_ok_button()->set_disabled(true);
		return;
	}
	if (varying_error_label->is_visible()) {
		varying_error_label->hide();
		add_varying_dialog->set_size(Size2(add_varying_dialog->get_size().x, 0));
	}
	add_varying_dialog->get_ok_button()->set_disabled(false);
}
void VisualShaderEditor::_varying_deleted() {