Just Enough Resources adds a JEI tab for mob drops, which gets removed completely if Abnormals Core and Buzzier Bees is also in the instance.

Here's the relevant error in the latest.log: https://gist.github.com/NillerMedDild/d687e2a0529732e91a8699c7364d8a4d

Related issue: way2muchnoise/JustEnoughResources#247

This appears to be on Buzzier Bees' side. Open an issue there: https://github.com/minecraftabnormals/Buzzier-Bees/issues/new