When AutoHUD is set to move the hud down instead of fade it, it also moves the pause menu down.

I have Sodium and Indium installed, as well as OneBar (which changes the hotbar HUD) and Create (which adds a button to the pause menu and also does some stuff to the hotbar). Full mod list can be posted on request.

Hi, I have found a way to implement my mixins more defensively by making use of another black magic project. This should theoretically make sure this kind of bug can never happen again, unless a mod does something very bad. I've published this as version 2.3 (pending on CurseForge). Please do test again if this happens to also resolve the remaining graphical glitches you've encountered. :)

Thank you for the report!

This bug can occur if another mod also changes the hotbar, and overrides the "move back" hook of AutoHUD. I am strongly assuming it's an incompatibility between OneBar and AutoHUD; will investigate later.

I have fixed this in AutoHUD 2.2.

Running both mods together will reveal OneBar whenever any of (health, armor, air, hunger) are set to change. You may use AutoHUD's options to configure their respective vanilla components. The OneBar handler inherits from those and should automatically reveal the OneBar whenever you wish.
Also OneBar's special experience bar renderer is working correctly.

Only caveat: OneBar appears to have a lot of other options that I did not delve into. Please do let me know if there are any other triggers that you wish would automatically reveal the OneBar again.

Sadly, it looks like there's a couple other mods in my pack that do weird things to the UI rendering.

...and there's currently 340 mods installed, and I suspect there's a lot of stuff that has non-obvious connections to UI stuff...

I don't have time to sort through it all, so I'll upload my CurseForge instance file here so you can test it:
Low Diesel-0.0.1.zip

I made this export after removing AutoHud from my modlist, so you can add a dev build or whatevs
good luck

Apologies; I don't mind fixing compatibility issues, but I also definitely do not have the time to search through 340 mods for you. Especially based on "one of these mods may cause some otherwise unspecified weird things".