Which Button Should I Push On This Toilet?

I went to Carpe Diem for dessert after lunch the other day (try the Biscoff gelato - it's delicious!), and decided to use their restroom. They've got a new slim-looking fancy toilet, and I wasn't sure which button to push!

The toilet flushing button(s) are the European kind, where one button releases a smaller amount of water into the bowl to flush a smaller amount of whatever is in the bowl. The larger button is for when there is a greater amount of whatever is in the bowl. Here's my dilemma: on this toilet, the buttons are the same size!

In Europe, IIRC, the smaller button is usually on the right, and the larger on the left, so I opted for the right-side button. The flow of water and resulting flush sounded almost "normal", so maybe I pushed the wrong one?  I don't know, and was too afraid to ask an employee.