[bug] Debug node corrupts workflow

[crux-03]

Describe the bug

When adding the Debug node anywhere in your workflow, the workflow will break upon next load with the following error:

Loading aborted due to error reloading workflow data

TypeError: can't access property "id", fromNode is undefined

Reproduction

1. Add Debug (mtb) node
2. Either save the workflow, then reopen it or simply swap to another workflow tab then back
3. Error appears

Expected behavior

Workflow should remain functional and accessible

Operating System

Linux

Comfy Mode

In a custom virtual env (venv, virtualenv, conda...)

Console output

[/mnt/nvme1/home_storage/crux/Software/ComfyUI/custom_nodes/comfy-mtb] | DEBUG -> Requesting face_restore with model None
[/mnt/nvme1/home_storage/crux/Software/ComfyUI/custom_nodes/comfy-mtb] | DEBUG -> Requesting upscale_models with model None
[/mnt/nvme1/home_storage/crux/Software/ComfyUI/custom_nodes/comfy-mtb] | DEBUG -> Resolved model path from folder_paths: /mnt/nvme1/home_storage/crux/Software/ComfyUI/models/upscale_models
[/mnt/nvme1/home_storage/crux/Software/ComfyUI/custom_nodes/comfy-mtb] | DEBUG -> Requesting face_restore with model None
[/mnt/nvme1/home_storage/crux/Software/ComfyUI/custom_nodes/comfy-mtb] | DEBUG -> Requesting upscale_models with model None
[/mnt/nvme1/home_storage/crux/Software/ComfyUI/custom_nodes/comfy-mtb] | DEBUG -> Resolved model path from folder_paths: /mnt/nvme1/home_storage/crux/Software/ComfyUI/models/upscale_models
[/mnt/nvme1/home_storage/crux/Software/ComfyUI/custom_nodes/comfy-mtb] | DEBUG -> Using cached styles (count: 3)
[/mnt/nvme1/home_storage/crux/Software/ComfyUI/custom_nodes/comfy-mtb] | DEBUG -> Adding font /mnt/nvme1/home_storage/crux/Software/ComfyUI/custom_nodes/comfy-mtb/data/font.ttf
[/mnt/nvme1/home_storage/crux/Software/ComfyUI/custom_nodes/comfy-mtb] | DEBUG -> Using cached fonts (count: 1)
FETCH ComfyRegistry Data: 15/120
FETCH ComfyRegistry Data: 20/120
FETCH ComfyRegistry Data: 25/120
FETCH ComfyRegistry Data: 30/120
FETCH ComfyRegistry Data: 35/120
FETCH ComfyRegistry Data: 40/120
FETCH ComfyRegistry Data: 45/120
FETCH ComfyRegistry Data: 50/120
...

Additional context

The console output above appeared before adding the Debug node. No console output when I got the error popup.

comfy_mtb version: 0.5.4