A stack overflow occurs when a farmer bee harvests wheat while XP from Harvest is installed.
It seems that the way the farmer bee harvests interacts with the on right click event in the simple harvest feature.

Steps to reproduce:
Place a farmer bee near fully grown wheat.
Wait for him to harvest wheat.
Crash.
crash-2021-02-01_15.11.45-server.txt

No error. I took the same exact collection of mods, moved bees out, right clicked some wheat, and it reported no error.

I believe it may be worth noting that on the server we are playing on, no errors are generated by right click harvesting with or without bees. The farmer bee causes the stack overflow crash by harvesting wheat and reading the crash log drew me to that conclusion that they must be interacting in some way.

The Farmer bee is sending a right click event on the block to be harvested (because you have Quark installed). XPFromFarming also handles the right click event. I'll add the mod to my dev env and see if I can figure out why it crashes.

I have the Quark simple harvest module disabled because it doesn't grant XP on harvest with XPFromHarvest. XPFH has its own simple harvest handler.

Managed to reproduce it once I disabled Quarks simple harvest and enabled XPFH.
The problem is with XPFH alone and happens if the harvesting drops a seed as well. You'll see the error in your log if you harvest yourself until you get a seed.
Kinda funny, Pams Harvestcraft has the exact same error when handling right click.

Real-Gecko/XPFromHarvest#7

Without PB installed, do you still get an error in the log when right click harvesting?