Seasickness on catamarans between islands?

I took a catamaran from Korcula to Split (with a stop in Hvar). I too kind of wondered about the ride, because I tend toward motion sickness. I wouldn't call it a smooth ride, but I managed. FYI, in bad weather, the catamarans may not run. The one the day after my trip was canceled due to a bad storm. (This was in October.)

I don't recall anyone getting seasick on the catamarans I've taken between islands in Croatia or the one I took between Croatia and Venice. But then the seas were relatively calm on all the days I've traveled.

If this is the boat that goes from Dubrovnik to Split, stopping at Hvar and Korcula, we took it in 2015. The boat is large. Possibly 200-300 people aboard. The day was nice and sunny, not hot, not much wind, few noticeable waves. I felt nothing in terms of boat movement. I enjoyed the trip - you could sit inside or outside on the back deck. Very fast trip. Not expensive.

Here's the theory on motion sickness I subscribe to: Your body reacts to the unusual motion (until you get used to it) by trying to fight it. Without realizing it, you use a lot of energy and your blood sugar drops - you feel sick. One of the first symptoms is sweat, because you are expending a lot of energy without realizing it.

Here's the theory on how to avoid it. Eat healthy foods, drink plenty of fluids, drinking something caffeinated is probably good too. When you get on the boat, find a seat with a clear view, fresh air and arm rests. You don't want a short field of view or to breath engine exhaust. Settle back deeply into the chair and use the armrests. You want to be stable without expending energy. Don't move around a lot. Move your eyes more than your head to see. Keep your focus on the horizon to the greatest extent possible. Breath deeply and regularly. If you can, take a nap.

I've found after you get used to it, you won't remember why you ever had motion sickness to start with.