Updated for Minecraft 26+!
A huge thanks to @MordorsElite and @mnowak32 for putting this update together, and the rigorous testing you put into it.
Changes
There are no user-facing changes - this update is primarily to bring it up to date with the latest minecraft versions. However the mod has been transferred across to use the new minecraft mod bindings.
Minecraft also requires that Java 25 be used for MC26+.
Updated for 1.21.11!
No new changes to be reported.
Updated for 1.21.9 and 1.21.10!!
Thanks to @weihx15 for the new Simplified Chinese translations.
Updated to 1.21.7!
Thanks to @theendercore for putting together this update.
Updated for 1.21.6!
Due to changes in the rendering engine, I've had to temporarily remove the z offset option. Unfortunately this means that the capacity bar is rendered on top of the item preview (if overlapping).
In the interest of providing this update sooner rather than later, I'll be deferring that fix for a later version (if necessary).

A minecraft fabric mod that displays a configurable icon indicating the contents of a shulker box, as well as a capacity bar.