When DimThread (https://www.curseforge.com/minecraft/mc-mods/dimthreads) is enabled OPAC does not seem to be able to protect correctly there appears to be no errors as its more of a threaded priority thing. This isn't neccisarily a bug for your plugin as it is DimThread's, hence the marking it as Bug and Feature Request, but if it would be possible to make OPAC thread safe and work with DimThread that would help preformance on servers a lot.

I'll consider it but it might get too complicated to be worth it for just mod compatibility.

that's fair, thank you for at least considering it! I didn't think it would be easy but figured i would bring it up since it has been a night and day difference in preformance, so much so i turn it on and people can open inventories again that would take nearly 1 minute to open.