here is the mod link:
https://www.curseforge.com/minecraft/mc-mods/hay-beds

read the description in the mod's page,I think they are kinda messing with vanilla sleep.

There is a config option to disable the sleep mechanics in better days. I am going to close this as I can't support mods messing with sleep at all, hence the ability to disable it entirely and still use the day/night length feature (which is the primary purpose of the mod) the sleep feature is just an extra.

What would the compat consist of? Unless they are messing with the vanilla sleep, there isn't anything to be done.