How to reproduce:
1. Open the user’s attached “MI 431 - Spartan Swashbucklers.zip” project
2. Open the “AINode” script (Assets/XnTools/XNAI/AINode.cs)
3. Add a breakpoint to the 41st or 46th line
4. Open “CaptainStrategy_XnAI_SO” script (Assets/___Scripts/_Captains CaptainStrategy_XnAI_SO)
5. Add a breakpoint to the 95th line
6. Attach the debugger to Unity
7. In the Project window, select “CS_JGB_Merchant_2_SO”
8. In the Inspector window in the “Child.XnTools.XnAI.AINode_Leaf_84” element, enable “Select Node”
9. Press  “__ XnAI –   SelectedNode - Add Decorator Parent” button
10. In the opened script editor, press the continue or step-into button
11. Observe the result

Expected result: No crash
Actual result: Crash

Reproducible with: 2021.3.23f1, 2022.2.16f1, 2023.1.0b13, 2023.2.0a11
Could not test with: 2020.3.47f1 (Errors after project downgrade)

Reproduced on: macOS 13.2.1 (Intel)
Not reproduced on: Windows 10 Pro

Notes:
Crash can appear after the 9th step
Reproducible with Rider and Visual Studio