[sirinsidiator]

I finally took the time to investigate the old "attempt to access a private function 'UseItem' from insecure code" error.
The issue can be reliably reproduced when opening a container via the keybind, closing it and then reopening it again without moving the mouse away from the item while AdvancedFilters is active.
I picked the code apart and disabled it part by part, line by line and finally found that the issue happens when PLAYER_INVENTORY:UpdateList is called from an addon.
More precisly it happens when self:ApplySort is called inside that method. My guess is that ZO_ScrollList_Commit breaks the secure context for the keybind when it autoselects the inventory item entry.

Maybe ZOS could add a new method RequestPlayerInventoryUpdate or something which allows us to call this from a secure context.
Until a better solution is found, I suggest addon authors use the following method instead of directly calling PLAYER_INVENTORY:UpdateList.

local function SafeUpdateList(object, ...)
    local isMouseVisible = SCENE_MANAGER:IsInUIMode()
 
    --if the mouse is visible, cycle its visibility to refresh the integrity of the control beneath it
    if isMouseVisible then HideMouse() end
 
    object:UpdateList(...)
 
    if isMouseVisible then ShowMouse() end
end
 
-- example usage for different inventories:
SafeUpdateList(PLAYER_INVENTORY, INVENTORY_BACKPACK)
SafeUpdateList(STORE_WINDOW)