If you start placing snow layers beside a snowblock and then you click on the side of the snow block, all the layers beside it will disappear except one.
To reproduce this bug, put a snow block or snow layers and then start putting snow layers next to it. them click on the side of the snow block like in the picture.
Duplicate of MC-8785, please use the search function to see if your bug has already been submitted. Currently over 50% of tickets are being closed as duplicate.