Making default new resource not "Show in menu"

I want a new resource that is made to default to having "Show in menu" unchecked.

I don’t think that’s one of the option in the Configuration, so you would probably need to use a plugin "OnBeforeDocFormSave", checking the mode to make sure it’s a new document and not an existing one being edited ($mode == ’new’), and setting $hidemenu to 1 (in the database, it’s ’hidemenu’, and 1 means it hides from the menu and 0 means it shows in the menu, just the opposite of what you might expect)