This is quite harmful to cats, please don't support doing this. There are a few reasons why putting a cucumber next to your cat while it's eating can be harmful:
It can startle your cat: Cucumbers are not a natural part of a cat's environment, and they may not be used to seeing them. Placing a cucumber suddenly next to your cat while it's eating can startle them and cause them to become frightened.
It can cause stress: Cats are creatures of habit and can become stressed if their routine is disrupted. Placing a cucumber next to your cat's food bowl can cause them to become anxious and stressed, which can lead to health problems.
It can create a negative association: If your cat becomes startled or stressed by the cucumber, they may start to associate negative feelings with their food bowl. This can lead to a reluctance to eat, which can cause a host of health problems over time.
It can be dangerous: If your cat is startled by the cucumber, they may leap away from their food bowl and injure themselves. They could also knock over their food bowl, spilling the food and water and creating a mess that could be harmful to them.
Overall, it's best to avoid placing cucumbers or any other unfamiliar objects near your cat's food bowl. Instead, let your cat eat in peace and avoid any unnecessary disruptions to their routine.