Pressing enter doesn't add mods?

I’m trying to add some new items to a world but some “vanilla” or pre-installed mods seem to refuse to add themselves to the list. Currently i’m trying to add the historical weapons but they refuse to go into the right section when I press enter. In addition mods that i’ve already installed like makeshift items can be removed by pressing enter, but its impossible to re-add them

whats going on here? I haven’t rebinded any keys

Sometimes random stuff you change was forgotten and now broke somthing else. Delete the whole thing and re-install. Reset the options and hope this solves the problem.