Any idea what this is, what is causing it and how to fix it?

https://imgur.com/a/AMf2J

It looks like a chunk error but from what I searched those are usually only single chunks.

This keeps happening quite often to me. Usually I think it happens at the same spots and sometimes it is pitch black. Disappears after quitting the world and going back in.

Are there any mods or mod settings that make this happen? I kind of suspect optifine but not sure.