For some reason, using this mod in tandem with Not Enough IDs causes the world to become a void instead of the normal 'biomes id only' fix. Not sure why this is happening. Structures still generate, but other than that there is nothing. Discovered this when I deleted my nether to use Future MC and wound up with a void.

Use roughlyenoughids it will fix it

I also have this issue and find that NEID 1.5.4.4 and JEID 1.0.3-55 have this issue. Was a NEID world (no version change for a year) and added JEID to gain other expanded ID lists like 1.13 however all new chunks (and new dimensions, and new worlds I make) are all void chunks IE nothing added to chunk it is just empty.

I tried rolling back either&both mods but it didn't work for me - might have other mods I would need to rollback, too.

I could provide saves (including a clean one without void chunks I fixed with MCEdit) if that would help?

Use roughlyenoughids it will fix it

Experienced the same problem, took a while to figure out which mod was the culprit. I'll check if downgrading to a previous version is possible and fixes the issue and post an update.

Experimenté el mismo problema, me tomó un tiempo descubrir qué mod era el culpable. Verificaré si es posible cambiar a una versión anterior, solucionaré el problema y publicaré una actualización.

Did you find a solution?

Kind of, its just not too great
iirc, you can load up both mods in your world, then make sure you load at least all the chunks you want to keep (the more, the better) then make a backup! (this is very important)

Load up your game with just JEID installed, your world will most likely break a bit (meaning blocks get swapped for others)
make a list of the blocks that are broken or got swapped

then load back into your backup with both mods, and remove as many of these breaking blocks as you can
your underground will probably be a complete mess so you might want to retrogen that (if that works)

Has anyone tried rolling back to an older version?

I am having this issue as well, does rolling back fix it?

Yep Im having the same Problem...
It would be great if there is way to make these 2 coexist, because i really dont want to lose my world :/

Is there any known combination of older versions of JEID and NEID that can coexist?

BetterFoliage is very broken. Like, verrrrrrrrrrrry.

I also have this issue and find that NEID 1.5.4.4 and JEID 1.0.3-55 have this issue. Was a NEID world (no version change for a year) and added JEID to gain other expanded ID lists like 1.13 however all new chunks (and new dimensions, and new worlds I make) are all void chunks IE nothing added to chunk it is just empty.

I tried rolling back either&both mods but it didn't work for me - might have other mods I would need to rollback, too.

I could provide saves (including a clean one without void chunks I fixed with MCEdit) if that would help?