I want to make a game almost like Minecraft using Three.js, but something that stumps me is how you have over 100,000 blocks in a world and the save files are not that big in size. How does Mojang make Minecraft world save files? (Any version of Minecraft works for me)

For instance, there is this unicorn world my little sister downloaded a long, long time ago for Bedrock edition, and it's just a pink world with tons of ice cream statues, rainbows, castles, Unicorns, and other stuff like that. It goes on for pretty much 2000 blocks in every direction (not including the Y axis) and that world is only 6 MB. How is this possible?

I downloaded the Minecraft coder pack to mod the game and decompile it, but how do I use it on Linux. Some sources seem to give specific directions, but they are not clear and they involve executing the .bat files. My Ubuntu does not recognize .bat file. How do I decompile a class file from changing a Minecraft version jar file to a zip and unzipping it? How do I decompile one of those class files using Minecraft coder pack? I have been wondering what at least some of the Minecraft source code looks like.

I would like to know if there is a way to build a js, a script for the following: https://www.chunkbase.com/apps/seed-map#seed=999&platform=bedrock_1_21&dimension=overworld&x=1214&z=-353&zoom=0.82 so that with a single key combination, or just by pressing a button, all the generated coordinates can be selected and displayed on the screen, if possible, functional for Tampermonkey

I have bought a hostinger minecraft server to play it with mods. In order to do so, I have to change server type. After that, change the forge version to 1.20.1 (My mod's version) and press "scan for new JARs". When finnished scanning, it only finds version 51.0.17, wich is valid for 1.21, but not for 1.20.1. What can i do to solve the problem?

I just want to play with mods, please help. I have asked ias and have talked with custommer attention service, but none of them can help me.

The exact error that apears when I try to start the server is this one: The Minecraft server stopped within 5 seconds of starting, this is not a fault with AMP - you should check your Minecraft servers log files to find out why it is unable to start.