### Godot version

4.1.beta1

### System information

macOS 13.3.1 mobile renderer

### Issue description

Trying to open and edit one of my visual shaders now consistently crashes Godot 4.1beta1. 

The shader was made and edited fine in earlier versions of Godot 4 and I'm not certain what is special with this shader (attached below for investigation). Opening and editing other visual shaders works fine for me. The only thing I can think of that this shader uses that other do not is the gradient node, though as I can't open it I'm not sure what else might be going on in it.

### Steps to reproduce

Open the attached visual shader (in any project)

### Minimal reproduction project

[ConnectBlendShader.tres.zip](https://www.lostminds.com/godot/ConnectBlendShader.tres.zip)
#include "curve_editor_plugin.h"
#include "canvas_item_editor_plugin.h"
#include "core/core_string_names.h"
#include "core/input/input.h"
#include "core/math/geometry_2d.h"
#include "core/os/keyboard.h"
#include "editor/editor_interface.h"
#include "editor/editor_node.h"
#include "editor/editor_scale.h"
#include "editor/editor_settings.h"
#include "editor/editor_undo_redo_manager.h"
#include "editor/gui/editor_spin_slider.h"
#include "scene/gui/flow_container.h"
#include "scene/gui/menu_button.h"
#include "scene/gui/popup_menu.h"
#include "scene/gui/separator.h"
CurveEdit::CurveEdit() {