Platform: Windows 10
Minecraft version: 1.21.4
Litematica version: 0.21.1
MaLiLib version: 0.23.1

When exiting the game in a custom dimension defined in a datapack whose json file is in a subfolder instead of the root of the namespace, the automatically generated filepath contains a slash. This leads part of the filename to be reinterpreted as a folder name, and because it might not exist, a FileNotFoundException is thrown.

Example:

• Dimension identifier example:root, filepath .minecraft/config/litematica/litematica_MyWorld_dim_example_root.json.tmp
• Dimension identifier example:foo/bar, filepath .minecraft/config/litematica/litematica_MyWorld_dim_example_foo/bar.json.tmp