[CRASH + BUG] Nether has rendering issues with shaders and crash related issue

[bscout9956]

Description of Issue

Nether sometimes (after switching shaders usually) makes the game/optifine only render a black depth buffer esque image.
If I go back to the overworld, I get a crash.

Steps to Reproduce

1. Load a world and enable Sildur's 1.28 or 1.23 High (or don't?). (both worked fine previously)
2. Go to the nether
   2.1 If the nether looks right, turn back to no shaders and then back to Sildurs (or any shader maybe?)
3. Either the game will be entirely a black depth buffer like image or hand items will look dark
4. Go back to the overworld
5. Switch shaders to off. You'll get a crash while "batching chunks" or JRE will stop responding*.

OptiFine Version

OptiFine_1.16.1_HD_U_G2
SHA-1: 87533B8AC0DFEB11241041F197F8F95C0FFA8C08

Installation Method

How did you install OptiFine? Did you use the included standalone installer, or did you drop the JAR file into your "mods" folder?
I dropped the jar into the mods folder. I use the Twitch Launcher to install Forge.

Fabric/Forge Version

Forge. Twitch Launcher installed. Version 32.0.98 (latest?)

Other Installed Mods

AppleSkin
Biomes O' Plenty
Collective
FastLeafDecay
VoxelMap (Forge)
GuiClock
GuiCompass
InventoryTweaks (latest for 1.16.1)
JEI

Log Files/Crash Reports

Any relevant log files. Drag and drop text files here to upload to GitHub directly, OR upload the complete contents to Pastebin. Log from Minecraft: https://pastebin.com/VRm9dDru
Forge Crash Report: https://pastebin.com/mchZQsAU

F3 Debug Screenshot

Prior Testing

If you've installed standalone:

• Does this happen in Vanilla without OptiFine?
  Impossible, shader issue.

If you've installed using Forge/Fabric:

• Does this happen without other mods installed?
  *Visual Glitches don't seem to happen (could be luck) but JRE stops working instead.

• Does this happen without any mods at all?
  Impossible to reproduce since shaders.

• Does this happen in OptiFine standalone?
  Yes.

• Does this happen in Vanilla without OptiFine?
  Impossible to reproduce since shaders.

• Have you tried using a binary search to find which mods cause this issue?
  No mods are in conflict. Optifine issue.

  • Does the issue still happen with only the remaining mods installed?
    Yes.

Additional Information

The crash log is probably the most helpful clue as to what may be going on. Removing other mods didn't make a difference.
Forge isn't the culprit.

Also, no forge and no other mods crashes like this, JRE hang:

[bscout9956]

Alternatively, one can launch the game in the Nether with Sildur's 1.28 to reproduce the visual glitches as it's seems to be a bit of an "edge case" situation.

[bscout9956]

Render Region issue?