BEFORE CONTINUING:

• Always check you are using the latest version of these mods and its dependencies
• Remove known problematic rendering mods such as Optifine, Sodium and others

Version-Loader

1.20.1-forge

Moonlight Lib Version

moonlight-1.20-2.9.17 and 1.20-2.9.12

Issue Detail

When loading Forge with Moonlight (alone or with other mods) it experiences a loading error during startup. The text of the error says "java.lang.ExceptionInInitializerError: null" The Java Edition Launcher reads out "Exit code: -1." I had played Minecraft only hours before experiencing this error. I haven't added, removed or edited any files or mods. The latest.log will be placed below. Also of note is that my wife has no issues loading either of these versions of Moonlight with either Forge 47.2.18 or 47.2.20 despite having the exact same mods and settings as me.

Log Attachment

latest.log

OPTIONAL: To Produce

1. Install Forge 47.2.18 or 47.2.20 to .minecraft/mods folder.
2. Install either version of Moonlight listed.
3. Launch Minecraft.

OPTIONAL: Which mods are affected?

Supplementaries as well as Supp Squared experience a java.lang.NoClassDefFoundError: Could not initialize net.mehvahdjukaar.moonlight.core.ClientConfigs
I've tried removing the Moonlight client files to let Forge rebuild them, and while that let Minecraft load, it loaded with all text on screen being replaced with placeholder rectangles and could not load into a world.

I've resolved the issue. After removing every single file in the mods folder, deleting the config folder in its entirety and then placing every mod back in the mod folder (as the newest versions of each), Minecraft now loads with no issues.