I added two of these splash guards, called “Tub Shower Splash Guard - 44″ Spraymaid”, which I purchased through Amazon for about $25 for the pair'  They really do keep water from splashing out from either end of the shower.  They were very easy to install, and keeping water out from outside the tub is very important.  Water damage can occur without you noticing it.   I think they only come in white, and they adjust for slightly out-of-square walls.

I'm going to try inserting a picture, cross your fingers…