Unable to fabricate items with certain materials combination

[michael-fakefish]

Reproduced in autumn-update-hotfix-3

Can be reproduced with vanilla item Spreader Flak Shells Box. Seems to be caused by two slots using the same material as an option and ignoring another suitable material by filling its slot instead of checking whether the condition for the material slot is already filled.

https://github.com/user-attachments/assets/45fa3453-102c-4086-a7d5-90d82b9af993

Discussed in https://github.com/FakeFishGames/Barotrauma/discussions/16327

^{Originally posted by A2ur3 July 29, 2025}

Disclaimers

• [X] I have searched the issue tracker to check if the issue has already been reported.
• [X] My issue happened while using mods.

What happened?

mod adds one new advmunition_tip item - tungsten pierceing coilgun ammo box requires 1 advmunition_tip and 2 advmunition_core steel bar has both advmunition_tip and advmunition_core tag you can not use tungsten to craft pierceing coilgun ammo box

Reproduction steps

1. this mod adds tungsten
2. try using tungsten and steel bar to craft pierceing coilgun ammo box

Bug prevalence

Happens every time I play

Single player or multiplayer?

Happens in both single player and multiplayer

-

No response

Version

v1.9.8.0 (Summer Update Hotfix 1)

-

No response

Which operating system did you encounter this bug on?

Windows

Relevant error messages and crash reports

No response