### Godot version

v4.2.rc.custom_build [702227129]

### System information

Godot v4.2.rc (702227129) - Debian GNU/Linux trixie/sid trixie - X11 - Vulkan (Forward+) - dedicated NVIDIA GeForce GTX 1060 6GB (nvidia) - AMD Ryzen 5 1600 Six-Core Processor (12 Threads)

### Issue description

Found a consistent crash when calling `hide()` from `_notification()`.
It does not happen if the call is deferred.

### Steps to reproduce

The `hide_test.gd` script has a boolean `cause_crash`. If it is true, hovering the mouse over the label crashes without an error in the Godot Editor Console. If it's false it hides the label as expected.

### Minimal reproduction project

[hide_crash.zip](https://github.com/godotengine/godot/files/13452818/hide_crash.zip)

if (gui.sub_windows.size() < 2) {
		return;
	}
	if (!gui.sub_windows[gui.sub_windows.size() - 1].window->get_flag(Window::FLAG_ALWAYS_ON_TOP)) {
		int index = gui.sub_windows.size() - 1;
		while (index > 0 && gui.sub_windows[index - 1].window->get_flag(Window::FLAG_ALWAYS_ON_TOP)) {
			--index;
		}
		if (index != (gui.sub_windows.size() - 1)) {
			SubWindow sw = gui.sub_windows[gui.sub_windows.size() - 1];
			gui.sub_windows.remove_at(gui.sub_windows.size() - 1);
			gui.sub_windows.insert(index, sw);
		}
	}
	for (int i = 0; i < gui.sub_windows.size(); i++) {
		RS::get_singleton()->canvas_item_set_draw_index(gui.sub_windows[i].canvas_item, i);
	}
}
void Viewport::_sub_window_register(Window *p_window) {