/run hooksecurefunc(MainMenuBarBackpackButton, "OnPlayerEnteringWorld", function(self) self:SetCountShown(false) self:UpdateFreeSlots() end) MainMenuBarBackpackButton:SetCountShown(false) MainMenuBarBackpackButton:UpdateFreeSlots()
or paste everything but the /run into the website addon.bool.no to create/download a small addon to do it automatically when you login.