Search the documentation for "ActionBarSlotType" to start with.
I have no idea what the previous command did but using that I found
SelectSlotSimpleAction *protected* (*[ActionBarSlotType|#ActionBarSlotType]* _actionType_, *integer* _actionId_, *luaindex* _actionSlotIndex_, *[HotBarCategory|#HotBarCategory]:nilable* _hotbarCategory_)
More then likely it did not break, it was significantly altered? Just thinking out loud as I look.
I can see GetItemCurrentActionBarSlot() in the Alias files.
https://github.com/esoui/esoui/blob/....lua#L739-L741
Maybe FindActionSlotMatchingItem(bagId, slotIndex) but I don't know if it has the same functionality.