ᐅ Are Drainage Slots Necessary in PVC Windows?

Hello, can someone tell me if these drainage slots in PVC windows are necessary? I am planning to build a new house, and the bottom frame will be mostly covered by the facing brickwork. This would also leave no space for the slots. Maybe the new windows don’t have these slots at all? Can someone help me?

In the windows I am familiar with and have installed, these "slots" are so-called "cleaning openings." When cleaning the inner frame, water can drain out through these openings. I have also observed that during heavy rain, rainwater can enter the frame directly onto the glass and then safely exit to the outside through these openings. In my opinion, sealing them could cause problems.