[0.18.12] Crash FluidBoxManager::save when saving

[tguzik]

Runtime game version: 0.18.12 (build 49842, win64, steam)
Map last saved by game version: 0.18.11-1 (steam)

Issue: Game crashes when trying to save the gamestate. Issue did not occur before the version upgrade.

Steps to reproduce:
1. Sync mods/Load the attached map ("LTS 0.18")
2. Either wait for autosave or just try to save the game manually
3. The game should crash to desktop when the progress bar is at about 40%

Let me know if i should upload the zipfile with the mods folder - it's kinda big, at about 100 MB (thanks texture mods :v ). All mods are at their most up-to-date versions, without any manual modifications

Edit: Still occurs after downgrade to 0.18.11 (via steam) - same message and same recreation steps.
Edit #2: Removing mod https://mods.factorio.com/mod/better-air-filtering seems to be a viable workaround on 0.18.12.

[Rseding91]

Does this still happen in the latest 0.18? There were a lot of changes around fluids in the meantime.