This MOD is working on my client.
Categories are not displayed for mods that do not contain _mod_category.
UI is added to the left side only for compatible mods, and the category is displayed.
Is there a mod that doesn't work? I want a more detailed situation.

Does it work now? It doesn't work for me. How can I fix it ?

Thank you. I think the way to insert the label is not bad either.

You can also make Splitters by setting empty options like so:

local emptyoptions = {{description="", data=false}}
local function Breaker(name)
return {
name=name,
options=emptyoptions,
default=false,
}
end