Hi, I'm the author of a mod called Scaling Feast. My mod requires that I cancel the RenderGameOverlayEvent.ElementType.FOOD to redraw the whole bar from scratch. This unfortunately has the side effect of completely stopping the armor toughness bar from rendering. Switching to RenderGameOverlayEvent.ElementType.AIR should prevent this issue altogether. This change shouldn't be too complicated; some other mods already draw their HUD elements on this event no problem. Here's a link to Tough as Nails' GitHub - they draw their HUD elements during the RenderGameOverlayEvent.ElementType.AIR event, which you can use as a resource if you'd like.

Actually, I have found a solution that works well. This issue is no longer relevant. Apologies