When both Detail Armor Bar and HWYLA Addon HorseInfo are loaded, the horse health bar renders incorrectly. This does not happen with only one of the two mods, and happens whether or not a version of WAILA/HWYLA/WTHIT is loaded.
This is in a fresh Minecraft instance and world:
MultiMC Log
image

I've cross reported this to HWYLA Addon Horseinfo, and will delete the report here if it turns out your mod is not at fault.

UPDATE: I have replicated the issue in a fresh instance with only DetailArmorBar, FabricLanguageKotlin and FabricAPI present.
MultiMC Log

When in creative mode, the horse's health renders correctly. I presume this is because DetailArmorBar (or the armor bar in general) is not called when in creative.

will fix in 1.3 :)

Resolved in 1.3 :>