### 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

/
edit_type = edit_type_fog;
		custom_mode_box->set_visible(false);
		varying_button->hide();
		mode = MODE_FLAGS_FOG;
	} else if (p_which == VisualShader::MODE_PARTICLES) {
		edit_type_standard->set_visible(false);
		edit_type_particles->set_visible(true);
		edit_type_sky->set_visible(false);
		edit_type_fog->set_visible(false);
		edit_type = edit_type_particles;
		if ((edit_type->get_selected() + 3) > VisualShader::TYPE_PROCESS) {
			custom_mode_box->set_visible(false);
		} else {
			custom_mode_box->set_visible(true);
		}
		varying_button->hide();
		mode = MODE_FLAGS_PARTICLES;
	} else {
		edit_type_particles->set_visible(false);
		edit_type_standard->set_visible(true);
		edit_type_sky->set_visible(false);
		edit_type_fog->set_visible(false);
		edit_type = edit_type_standard;
		custom_mode_box->set_visible(false);
		varying_button->show();
		mode = MODE_FLAGS_SPATIAL_CANVASITEM;
	}
	visual_shader->set_shader_type(get_current_shader_type());
}
Size2 VisualShaderEditor::get_minimum_size() const {