Minecraft Fabric 1.20.8
Also requires the Fabric-API.
Ever since Mojang updated their command framework to Brigadier, commands are case-sensitive.
If you are as incompetent as me, you will hold the SHIFT key for too long when typing / and thus causing the next letters to be capital too.
Which breaks the command execution and tab completion.
This mod forces commands (not subcommands/arguments), to be lower cased.
You won't be able to type upper-case in the root command anymore.
Which fully prevents the issue from happening.
You will NOT be able to type any command with uppercase letters anymore!
Subcommands and arguments are not affected.
This mod only works on servers / with plugins that do things right and register only lower-case commands.