Undoing guide creation makes empty array in scene file

[KoBeWi]

Godot version

4.2 dev3

System information

Windows 10.0.19045 - Vulkan (Forward+) - dedicated NVIDIA GeForce GTX 1060 (NVIDIA; 30.0.15.1403) - Intel(R) Core(TM) i7-7700HQ CPU @ 2.80GHz (8 Threads)

Issue description

Basically variation of #33995

Steps to reproduce

1. Open 2D scene
2. Drag a guide
3. Undo
4. Save

Minimal reproduction project

N/A

[coumcashier]

relevant code

godot/editor/plugins/canvas_item_editor_plugin.cpp

Line 1143 in 6758a7f

if (drag_type == DRAG_V_GUIDE) {