No such warning that I saw came on the 3kg container of Vanish, formerly known as Napi-San, a product sold here by Reckitt Benckiser, perhaps formerly Reckitt Coleman, a world wide multinational giant.
I have helpfully put a mark on our new container of Vanish, where the level of detergent reaches in the container. Some considerable settling of contents has happened, like nearly half the container. Too much time on my hands? I did weigh it and it was over its advertised 3kg weight.