EVENT ACTION SLOTS FULL UPDATE
From ESOUI Wiki
EVENT_ACTION_SLOTS_FULL_UPDATE (number eventcode, bool isHotbarSwap)
This event fires whenever the game requests that the UI do a full refresh of the hotbar action slots at the bottom of the screen (5 abilities, 1 ultimate, 1 quickslot). The variable isHotbarSwap is true if the event was triggered by a weapon swap, false otherwise.