Fixing a memory leak in 0.2.6 is significant and should probably be backported to mc1.20.1 which is currently the most popular modding version for newer versions of Minecraft.

The memory leak in 0.2.6 that was fixed was in fact a bug in Krypton, for a fix to an issue that was actually in Fabric API.

I am not going to "backport" to older versions of Minecraft. I simply do not have the time to do this.

Also, you can just use an older version of the Fabric API to work around the issue anyway.