I was attempting to use portals and world stacking to travel to the far lands. Utilizing the 8:1 nether ratio. I made it to -11600 before I found a point that allowed me to get onto the nether roof, rather than the overworld.

Are you using Forge?

Yes, I'm running this specific jar file.
immersive-portals-0.18(forMc1.15withForge)

The vertical connecting portal's width is 233333. I can change it to bigger

The vertical connecting portal's width is 233333. I can change it to bigger

you could change it to follow the player's position so that they can never reach the edge

There would need to be a portal per player in that case. I'm not sure what would happen if two or more portals overlapped.

There would need to be a portal per player in that case. I'm not sure what would happen if two or more portals overlapped.

not exactly, but maybe it would be less complicated to just use a much bigger size, like 1000000000 (Minecraft worlds are usually about 30 million blocks in either direction)

Worth a shot. It'd take at least, 60,000,001
I'm not sure what'd happen if you cross the 30 million limit.

I'm not sure what'd happen if you cross the 30 million limit.

Nothing. That's just the default world border but Minecraft worlds are infinite.

@qouteall perhaps you could automatically use the size of the world border?