This shows what happens:
https://github.com/user-attachments/assets/e7be09d4-3a0f-4a9a-a6c7-bdca5c2c0ee1

It's not related to whatever transmog is selected or saved. If I re-open the window after the above is closed, it breaks again.

Hi again! It's been fixed in the latest update.

Awesome, thanks!!

Is there any procedure to trigger it? It seems fine on my end.

It seems to only trigger when (at least on Destruction) I have "Skull of the Man'ari" as part of my saved outfit in the off-hand transmog slot. Any non-artefact slot works fine.