1.21.6
While we wait for JackFred2 to release 1.21.5, counting on @TimHoogervorst for 1.21.6 (https://github.com/TimHoogervorst/ChestTracker)
will take a look at it this Sunday, but no promises though, since i am still not a java dev ;)
Sadly some significant changes were made in the rendering system in 1.21.6, so i won't be able to update this one.
I've got almost 30 years of Java Experience, though I've not messed with any mods in a long time. If I can get some time, I'll setup a build environment and see if anything's obvious.
maybe use Architectury API ? i saw there is a temporary port to where is it that uses that.
https://github.com/JackFred2/ChestTracker/pull/304