Crash on import with UDIM when UV vertex is placed across 2 UDIM tiles #1870

Issue still not solved #1163 but I cannot reopen it

here is another model that results in a crash when seperating by udim:

SimpleCollectionOfficeChair.zip

ArmorPaint version:
I tried 10alpha and 09 from gumroad

OS / GPU model:
Win 10
3080 Ti

Issue description:

When importing the obj mesh and selecting seperating by UDIM the program just crashes without error message.
Importing it with selecting seperate by object works.

Steps to reproduce:

1. Download the model
2. Open Armor Paint
3. Import mesh
4. Set to seperate by UDIM
5. Click import
6. Crash