FYI In the 1.12 update, downward flowing water no longer "pushes" down on glass & leaves. (and maybe others) See: VIDEO
True, but this has been the case for quite a while already. The "underwater water texture" got changed in 1.9.
I'm talking more about the effects water has on player/mobs when flowing down beside a block. This was a change on 1.12. I use leaf blx in the spawning area for a guardian farm and in 1.11 the water pushed down guardians & reduced wandering. In 1.12, they don't have the same effect. You can test by making 3, one wide holes a few blx high one out of glass, one out of leaves & one out of stone (or any solid block). Place water in the top hole and jump in. You'll see the difference in trying to swim up, and the speed you go down.
