So prior to this, I've only ever had polyester shower curtains that I laundered in the washing machine occasionally and would have to replace when the mold stains became fixed.
As a more eco alternative, for the first time in my life, we have invested in a hinged, frameless, glass shower screen. We squeegee it religiously after every shower but it has become marked with limescale nonetheless and the seal at the bottom is starting to grow mould.
Full disclosure: it is screening an electric shower over our bath.
How do you clean yours?