That is because the water level is low. the cat must have tried to drink water the usual way but u might have noticed that the edges of the container are sharp and would have hurt him/her . Hence this way of drinking water...the cat must be very thirsty
My other cat drinks from it all the time. I also have other tubs of water around the flat such as the white one in the corner of the video and a bowl outside. This is also my neighbours cat. I let all the street cats in for food and water. But I can't afford it anymore and I'll have to leave. But believe what you want. God knows. I'll have to stop letting them in anyways.
