### 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

/
preview_showed = false;
	preview_window->hide();
	preview_shader->set_pressed(false);
}
void VisualShaderEditor::_preview_size_changed() {
	preview_vbox->set_custom_minimum_size(preview_window->get_size());
}
static ShaderLanguage::DataType _visual_shader_editor_get_global_shader_uniform_type(const StringName &p_variable) {
	RS::GlobalShaderParameterType gvt = RS::get_singleton()->global_shader_parameter_get_type(p_variable);
	return (ShaderLanguage::DataType)RS::global_shader_uniform_type_get_shader_datatype(gvt);
}
void VisualShaderEditor::_update_preview() {