1. I've got an error when tried to create UIDropDownMenu in Vanilla 1.12.1:

    Error: attempt to call global UIDropDownMenu_CreateInfo (a nil value)
    AddOn: ThievesTools
    File: ThievesTools.lua
    Line: 58
    Count: 1

    My function in this file:

    local function initialize(self, level)
        local info = UIDropDownMenu_CreateInfo() -- line 58
        for k,v in pairs(items) do
            info = UIDropDownMenu_CreateInfo()
            info.text = v
            info.value = v
            info.func = OnClick
            UIDropDownMenu_AddButton(info, level)

    What I need to do to remove this error and makes my DropDownMenu works?