Revert MC-101556
Reverts the "fix" for MC-101556. Makes nether portals/chunk loaders work properly again.
About this Mod
Reverts the "fix" for MC-101556 (only affects 1.21.5).
Makes nether portals/chunk loaders work properly again.
Please note that the "fix" for MC-101556 was reverted by Mojang in 25w16a (1.21.6) and the mod is no longer required in these versions.
The mod itself is extremely minimalistic and only a single line of code was patched.
Available Versions
How to Install Revert MC-101556 on Your Server
Order Server
Order a Minecraft Java server with at least 3 GB RAM (4 GB recommended).
Set fabric Loader
In the panel under "Egg", select the fabric loader and matching Minecraft version (1.21.5).
Install Mod
Open the mod browser in the dashboard and search for "Revert MC-101556". Click "Install" – done! Alternatively, upload the .jar via SFTP to the /mods folder.
Compatibility
Mod Loaders
Minecraft Versions
1.21.5
Server-side
✓ RequiredRecommended RAM
4 GB(min. 3 GB)Frequently Asked Questions
Revert MC-101556 server crashes on startup – what to do?
Most common cause: wrong fabric version or insufficient RAM. Check the server log (latest.log) for "OutOfMemoryError" or "Mixin" errors. With Mado Hosting: ensure at least 3 GB RAM is allocated and the loader matches the mod version (1.21.5). You can switch loaders with one click in the panel.
Is Revert MC-101556 compatible with fabric?
Revert MC-101556 officially supports fabric for Minecraft 1.21.5. The Mado dashboard automatically detects incompatible loader combinations.
Server lagging with Revert MC-101556 – how to optimize performance?
Recommended RAM: 4 GB (per 8 players). Use /spark profiler to check if Revert MC-101556 consumes the most tick time. Common fixes: reduce server view-distance to 8-10, install "performant" or "starlight" as supplementary mods on Forge. With Mado Hosting, your server runs on NVMe SSDs with dedicated CPU cores for minimal latency.
Similar Mods
Rent Modded Server
Install Revert MC-101556 with just one click on your server.