Placing a sandstone next to another sandstone makes invisible blocks

I was placing some sandstone next to each other against a sponge pillar, and the blocks placed at the upper part becomes invisible except the fist block which is half invisible

I can reproduce it sometimes by pouring water in a 9 long channel with a sponge drop at the end (7+hole+sponges) as seen in the background in the image attached.

The blocks returns visible after relogging.