• Yes, I'm sure this problem isn't because my game ran out of RAM.

Describe the bug
CustomSkinLoader is reported as a duplicate only when using GDLauncher. For details (reproduction steps, screenshots, system info) see gorilla-devs/GDLauncher#1279.

Details
Please fill out the blanks below:
Modpack Version: 1.35.2.118.1
Did you add or remove mods? No
Did you edit any config or script? No
Using shaders? [Write 'Default' if you are using default shader, if you are not using the default shader please write the name of the shader you are using.] Default
Singleplayer, LAN game or server pack? N/A

Additional context
Just filing this here for tracking purposes on the launcher's GitHub. It's likely not your problem.