Peaceful mode will auto set to Normal... And ... I was Killed by a creeper... Hahahaha...
version 3.2a

I've had the same, and found a workaround for now, if you set your game to allow cheats, lock the difficulty with the lock button in the menu, and then if you want to change it use the /difficulty command to change it.

For me it switch always to hard... oO
I change to peaceful...but it wont work.

In default options config the difficult is to easy....in the normal option file its on peaceful....but in game...its hard.... why?

Oh and i CANT lock it on peaceful or another because it switches ALWAYS on hard....i klick easy...lock...and its lock on hard....i switch to peaceful...lock....hard too....

Uh I find something... JustEnoughDimensions Pack Cause this Problem and the BonusChest comeback when i exclude it.

I have edited the DefaultOptions config to exclude setting a gamemode and the JustEnoughDimensions thing might have been related I can see that. I planned on updated the JED config anyway for next update

I disabled the default options mod in my own version, since I was looking for the bug myself and it kept persisting, it could be that default option leaves stuff behind after being disabled but that was the first thing I removed to try and fix

related to maruohon/justenoughdimensions#14
bonus chest also fixed in mod ver 1.5.5

will be resolved in next pack update