RenderHudCallback was added some time ago but I think mod devs would like some more flexiblity with a render callback at a different stage of rendering the in game hud.

A few ideas for some spots where some callbacks could be useful:

• Before/After ChatHud
• Before/After Hotbars (hearts, armor bar, item hotbar)
• Before/After Pumpkin overlay
• Before/After Vignette.

Also this is issue #1000. The 1000th issue on fabric api is definitely an achievement to reach, but I had to use the issue number for something lol.

#1000 issue, but no activity.. #MOREHUDRENDEREVENTS

Should these be raw Callbacks like the current RenderHudCallback, or should one be able to cancel the rendering of the associated HUD element (Similar to the new BlockBreakEvent) or even one be able to even move around vanilla HUD elements?

These are some question that came to my mind that need to be discussed before one can start implementing this.

Thoughts on the last after thinking a bit:
I don't think this is feasible or atleast I have no idea on how to handle multiple mods with it.
If one wants to move vanilla HUD elements they should probably cancel their rendering and render them again themselves (Is this better?)
Although that would of course require the second aspect: being able to cancel the rendering of HUD elements.