I have been having a problem in a world. Whenever i turn on the borders, it doesn't display nice straight lines like in my creative testing world. it makes a lot of weird shapes that i can't distinguish biomes from (See picture attachment)f

https://bugs.mojang.com/browse/MC-209558

My only thoughts so far are that those borders look like the biome borders in the nether.

What mods are you using?
What version of Minecraft, Forge, and BiomeBorderViewer are you using?
Can you take another screenshot with the F3 menu open?

I am only using the BiomeBorderViewer Mod.

Minecraft is on 1.16.4, which might be an issue? Forge is running on version 1.16.4-forge-35.0.3

The mod file is called "biomeborderviewer-1.16.4-7.0.0.0.jar"

Not that i know of, no.

Do you have any datapacks installed that modify worldgen?

Would the seed be sufficient?

Can you send me the world somehow?

Unlikely. A zip containing the entire world folder is most likely to be useful.

Does the mod not function on servers?

This is a client side mod. Installing it on the server might cause problems, but it shouldn't.

I am running it Client sided, but i am on a server. I might be able to get the world folder, but i don't think the owner would see this as important enough to bother with it

My guess is that the server has a datapack installed that changes worldgen. Without access to the world folder, I can't tell if this is a bug or not.
If you get on your own world and go to the nether, you should see biome borders similar to the ones you posted above.

Oh alright. There might be one that i am not aware of. I think i am gonna try to just use the F3 menu then. Thank you for responding though. Great mod!

After testing this I found that the blocks at y=0 are still the exact correct border on a server, so that could be a make do fix for now until it is fixed in the game itself.