'Ghost' blocks in End

When I entered the End in my test world, I noticed some ghostly, transparent, magenta blocks that moving with me. I could see them when looking in the south-west direction on the blocks at y=59, but the ghost could only be seen on y=64-69. When not on that elevation the ghost was not there, and could only be seen on the End Stone

Steps to Reproduce:
1.Go to End Dimension
2. While player is on y=64-69 look in SW onto End Stone on y=59