Editor: Random crash on save with Qt6

OpenMW-CS randomly crashes on saving a plugin. Here's an example of a crash log: openmw-cs-crash.log Making a patch for Beautiful Cities of Morrowind and Corprusarium - Sorrow Heart of Tel Fyr. Mostly moving objects in interiors. Can attach a WIP file, if needed.

OS: Ubuntu 24.04 x64, version: 1aa4ef02.

OpenMW-CS built against QT6.

While loading BCoM, OpenMW-CS reports

Logic error: cell index out of bounds
Logic error: cell index out of bounds
Logic error: cell index out of bounds
Logic error: cell index out of bounds
Attempt to delete a non-existent reference - RefNum index 242625, refID senyndie, content file index 0
Attempt to delete a non-existent reference - RefNum index 242626, refID ultis salam, content file index 0

if it's relevant.