When using ToroHealth Damage Indicators with Complementary Reimagined (r5.4) in 1.21.1 on Fabric, the portion of the in-world health bars above mobs that shows the current health glows (in the same way that ores and whatnot do with emissive ores). The other portion, the missing current health from the max health, doesn't glow. I think the shaders are mistakenly treating the current health portion of the bar as some sort of emission-needing object.

Actually no, it seems the entire bar glows. At first it only looked like the current health portion because it's a brighter color.