THIS AFFECTS BOTH SURVIVAL AND CREATIVE MODE. Basically this bug shows the outline of "air blocks" when viewing gaps between blocks above water. The images attached show what I mean.
To Reproduce (MAKE SURE YOU ARE UNDERWATER):
1. Have a block on the ground, in between, and above, in a 1x3 tower. Other blocks surrounding the middle are optional. They only enhance the look of this glitch
2. Delete the middle block. You can leave some of the blocks in the middle surrounding that now empty space. You should have an air block in that little gap.
3. Go to the surface of the water and look at that area. There will now be a black outline of that air block
My description on how to reproduce the visual glitch isn't the clearest since I don't really know how to explain it fully. Hopefully the images show what I mean....
Image 1: Shows the visual glitch from above water
Image 2: Shows what causes the visual glitch (Hard to see... not very bright under water) The area that has the "air block" is in the center. You can faintly see flowing water moving past the area.