When I go in spectator mode, the cross-hairs are hidden until I look at the 1.14 blocks. The video (the link) explains it best. The blocks it effects are all the full non-transparent blocks and the grindstone as well as the stonecutter.

https://www.dropbox.com/s/3d09qykth6elzlc/Minecraft%201.14.2%206_11_2019%204_34_53%20PM.mp4?dl=0