### Godot version

master ([06ccbfe](https://github.com/godotengine/godot/commit/06ccbfe8eec6e840db3df2360dc2804386f940b8))

### System information

PopOS 22.04

### Issue description

Sometimes the doc page is broken when the engine is closed and then restarted.
Closing the doc and opening it again fixes it.

![2023-05-27_22-15](https://github.com/godotengine/godot/assets/3624853/ed202a55-03e8-420a-bc1c-ccfc7f7cd02a)


### Steps to reproduce

- Open a documentation page for any node
- Restart Godot

### Minimal reproduction project

NA

EDIT : Added the commit hash @Calinou 
};
	struct ItemRainbow : public ItemFX {
		float saturation = 0.8f;
		float value = 0.8f;
		float frequency = 1.0f;
		ItemRainbow() { type = ITEM_RAINBOW; }
	};
	struct ItemBGColor : public Item {
		Color color;
		ItemBGColor() { type = ITEM_BGCOLOR; }
	};
	struct ItemFGColor : public Item {
		Color color;
		ItemFGColor() { type = ITEM_FGCOLOR; }
	};
	struct ItemCustomFX : public ItemFX {
		Ref<CharFXTransform> char_fx_transform;
		Ref<RichTextEffect> custom_effect;
		ItemCustomFX() {
			type = ITEM_CUSTOMFX;
			char_fx_transform.instantiate();
		}
		virtual ~ItemCustomFX() {
			_clear_children();
			char_fx_transform.unref();
			custom_effect.unref();
		}
	};
	ItemFrame *main = nullptr;