Affected Versions (Do not use "latest")::

• Minecraft: 1.12.2 Optifine
• ArmorPlus: 1.12.2-11.28.0.69
• TheDragonLib: 1.12.2-5.3.0
• GeckoLib: ??
• Forge: 14.23.5.2860
• Just Enough Items (JEI): 4.16.1.302

Affected Side (Client or Server):

• Client
• Server

Describe the issue:
By leaving the workbench placed in the world, the world won't load again.

Additional notes:
I'm using Project Ozone 3 modpack.

By using MCEdit to remove the workbench, the world can be fixed.

Confirmed here:
Cazadorsniper/PO3#1412
Cazadorsniper/PO3#1260

The crash report (via. pastebin/gist/etc): https://pastebin.com/kjMQYm3W

Hey there, thanks for the report!

Unfortunately the 1.12.2 version is no longer supported (Support stopped on May 10, 2020), following the steps shown in those issue reports should help you fix the issue.